freebsd-nq/module/zfs/spa_stats.c

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Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
#include <sys/zfs_context.h>
#include <sys/spa_impl.h>
/*
* Keeps stats on last N reads per spa_t, disabled by default.
*/
int zfs_read_history = 0;
/*
* Include cache hits in history, disabled by default.
*/
int zfs_read_history_hits = 0;
/*
* Keeps stats on the last N txgs, disabled by default.
*/
int zfs_txg_history = 0;
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
/*
* ==========================================================================
* SPA Read History Routines
* ==========================================================================
*/
/*
* Read statistics - Information exported regarding each arc_read call
*/
typedef struct spa_read_history {
uint64_t uid; /* unique identifier */
hrtime_t start; /* time read completed */
uint64_t objset; /* read from this objset */
uint64_t object; /* read of this object number */
uint64_t level; /* block's indirection level */
uint64_t blkid; /* read of this block id */
char origin[24]; /* read originated from here */
uint32_t aflags; /* ARC flags (cached, prefetch, etc.) */
pid_t pid; /* PID of task doing read */
char comm[16]; /* process name of task doing read */
list_node_t srh_link;
} spa_read_history_t;
static int
spa_read_history_headers(char *buf, size_t size)
{
(void) snprintf(buf, size, "%-8s %-16s %-8s %-8s %-8s %-8s %-8s "
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
"%-24s %-8s %-16s\n", "UID", "start", "objset", "object",
"level", "blkid", "aflags", "origin", "pid", "process");
return (0);
}
static int
spa_read_history_data(char *buf, size_t size, void *data)
{
spa_read_history_t *srh = (spa_read_history_t *)data;
(void) snprintf(buf, size, "%-8llu %-16llu 0x%-6llx "
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
"%-8lli %-8lli %-8lli 0x%-6x %-24s %-8i %-16s\n",
(u_longlong_t)srh->uid, srh->start,
(longlong_t)srh->objset, (longlong_t)srh->object,
(longlong_t)srh->level, (longlong_t)srh->blkid,
srh->aflags, srh->origin, srh->pid, srh->comm);
return (0);
}
/*
* Calculate the address for the next spa_stats_history_t entry. The
* ssh->lock will be held until ksp->ks_ndata entries are processed.
*/
static void *
spa_read_history_addr(kstat_t *ksp, loff_t n)
{
spa_t *spa = ksp->ks_private;
spa_stats_history_t *ssh = &spa->spa_stats.read_history;
ASSERT(MUTEX_HELD(&ssh->lock));
if (n == 0)
ssh->private = list_tail(&ssh->list);
else if (ssh->private)
ssh->private = list_prev(&ssh->list, ssh->private);
return (ssh->private);
}
/*
* When the kstat is written discard all spa_read_history_t entires. The
* ssh->lock will be held until ksp->ks_ndata entries are processed.
*/
static int
spa_read_history_update(kstat_t *ksp, int rw)
{
spa_t *spa = ksp->ks_private;
spa_stats_history_t *ssh = &spa->spa_stats.read_history;
if (rw == KSTAT_WRITE) {
spa_read_history_t *srh;
while ((srh = list_remove_head(&ssh->list))) {
ssh->size--;
kmem_free(srh, sizeof (spa_read_history_t));
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
}
ASSERT3U(ssh->size, ==, 0);
}
ksp->ks_ndata = ssh->size;
ksp->ks_data_size = ssh->size * sizeof (spa_read_history_t);
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
return (0);
}
static void
spa_read_history_init(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.read_history;
char name[KSTAT_STRLEN];
kstat_t *ksp;
mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL);
list_create(&ssh->list, sizeof (spa_read_history_t),
offsetof(spa_read_history_t, srh_link));
ssh->count = 0;
ssh->size = 0;
ssh->private = NULL;
(void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa));
ksp = kstat_create(name, 0, "reads", "misc",
KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL);
ssh->kstat = ksp;
if (ksp) {
ksp->ks_lock = &ssh->lock;
ksp->ks_data = NULL;
ksp->ks_private = spa;
ksp->ks_update = spa_read_history_update;
kstat_set_raw_ops(ksp, spa_read_history_headers,
spa_read_history_data, spa_read_history_addr);
kstat_install(ksp);
}
}
static void
spa_read_history_destroy(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.read_history;
spa_read_history_t *srh;
kstat_t *ksp;
ksp = ssh->kstat;
if (ksp)
kstat_delete(ksp);
mutex_enter(&ssh->lock);
while ((srh = list_remove_head(&ssh->list))) {
ssh->size--;
kmem_free(srh, sizeof (spa_read_history_t));
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
}
ASSERT3U(ssh->size, ==, 0);
list_destroy(&ssh->list);
mutex_exit(&ssh->lock);
mutex_destroy(&ssh->lock);
}
void
spa_read_history_add(spa_t *spa, const zbookmark_phys_t *zb, uint32_t aflags)
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
{
spa_stats_history_t *ssh = &spa->spa_stats.read_history;
spa_read_history_t *srh, *rm;
ASSERT3P(spa, !=, NULL);
ASSERT3P(zb, !=, NULL);
if (zfs_read_history == 0 && ssh->size == 0)
return;
if (zfs_read_history_hits == 0 && (aflags & ARC_FLAG_CACHED))
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
return;
srh = kmem_zalloc(sizeof (spa_read_history_t), KM_SLEEP);
strlcpy(srh->comm, getcomm(), sizeof (srh->comm));
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
srh->start = gethrtime();
srh->objset = zb->zb_objset;
srh->object = zb->zb_object;
srh->level = zb->zb_level;
srh->blkid = zb->zb_blkid;
srh->aflags = aflags;
srh->pid = getpid();
mutex_enter(&ssh->lock);
srh->uid = ssh->count++;
list_insert_head(&ssh->list, srh);
ssh->size++;
while (ssh->size > zfs_read_history) {
ssh->size--;
rm = list_remove_tail(&ssh->list);
kmem_free(rm, sizeof (spa_read_history_t));
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
}
mutex_exit(&ssh->lock);
}
/*
* ==========================================================================
* SPA TXG History Routines
* ==========================================================================
*/
/*
* Txg statistics - Information exported regarding each txg sync
*/
typedef struct spa_txg_history {
uint64_t txg; /* txg id */
txg_state_t state; /* active txg state */
uint64_t nread; /* number of bytes read */
uint64_t nwritten; /* number of bytes written */
uint64_t reads; /* number of read operations */
uint64_t writes; /* number of write operations */
uint64_t ndirty; /* number of dirty bytes */
hrtime_t times[TXG_STATE_COMMITTED]; /* completion times */
list_node_t sth_link;
} spa_txg_history_t;
static int
spa_txg_history_headers(char *buf, size_t size)
{
(void) snprintf(buf, size, "%-8s %-16s %-5s %-12s %-12s %-12s "
"%-8s %-8s %-12s %-12s %-12s %-12s\n", "txg", "birth", "state",
"ndirty", "nread", "nwritten", "reads", "writes",
"otime", "qtime", "wtime", "stime");
return (0);
}
static int
spa_txg_history_data(char *buf, size_t size, void *data)
{
spa_txg_history_t *sth = (spa_txg_history_t *)data;
uint64_t open = 0, quiesce = 0, wait = 0, sync = 0;
char state;
switch (sth->state) {
case TXG_STATE_BIRTH: state = 'B'; break;
case TXG_STATE_OPEN: state = 'O'; break;
case TXG_STATE_QUIESCED: state = 'Q'; break;
case TXG_STATE_WAIT_FOR_SYNC: state = 'W'; break;
case TXG_STATE_SYNCED: state = 'S'; break;
case TXG_STATE_COMMITTED: state = 'C'; break;
default: state = '?'; break;
}
if (sth->times[TXG_STATE_OPEN])
open = sth->times[TXG_STATE_OPEN] -
sth->times[TXG_STATE_BIRTH];
if (sth->times[TXG_STATE_QUIESCED])
quiesce = sth->times[TXG_STATE_QUIESCED] -
sth->times[TXG_STATE_OPEN];
if (sth->times[TXG_STATE_WAIT_FOR_SYNC])
wait = sth->times[TXG_STATE_WAIT_FOR_SYNC] -
sth->times[TXG_STATE_QUIESCED];
if (sth->times[TXG_STATE_SYNCED])
sync = sth->times[TXG_STATE_SYNCED] -
sth->times[TXG_STATE_WAIT_FOR_SYNC];
(void) snprintf(buf, size, "%-8llu %-16llu %-5c %-12llu "
"%-12llu %-12llu %-8llu %-8llu %-12llu %-12llu %-12llu %-12llu\n",
(longlong_t)sth->txg, sth->times[TXG_STATE_BIRTH], state,
(u_longlong_t)sth->ndirty,
(u_longlong_t)sth->nread, (u_longlong_t)sth->nwritten,
(u_longlong_t)sth->reads, (u_longlong_t)sth->writes,
(u_longlong_t)open, (u_longlong_t)quiesce, (u_longlong_t)wait,
(u_longlong_t)sync);
return (0);
}
/*
* Calculate the address for the next spa_stats_history_t entry. The
* ssh->lock will be held until ksp->ks_ndata entries are processed.
*/
static void *
spa_txg_history_addr(kstat_t *ksp, loff_t n)
{
spa_t *spa = ksp->ks_private;
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
ASSERT(MUTEX_HELD(&ssh->lock));
if (n == 0)
ssh->private = list_tail(&ssh->list);
else if (ssh->private)
ssh->private = list_prev(&ssh->list, ssh->private);
return (ssh->private);
}
/*
* When the kstat is written discard all spa_txg_history_t entires. The
* ssh->lock will be held until ksp->ks_ndata entries are processed.
*/
static int
spa_txg_history_update(kstat_t *ksp, int rw)
{
spa_t *spa = ksp->ks_private;
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
ASSERT(MUTEX_HELD(&ssh->lock));
if (rw == KSTAT_WRITE) {
spa_txg_history_t *sth;
while ((sth = list_remove_head(&ssh->list))) {
ssh->size--;
kmem_free(sth, sizeof (spa_txg_history_t));
}
ASSERT3U(ssh->size, ==, 0);
}
ksp->ks_ndata = ssh->size;
ksp->ks_data_size = ssh->size * sizeof (spa_txg_history_t);
return (0);
}
static void
spa_txg_history_init(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
char name[KSTAT_STRLEN];
kstat_t *ksp;
mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL);
list_create(&ssh->list, sizeof (spa_txg_history_t),
offsetof(spa_txg_history_t, sth_link));
ssh->count = 0;
ssh->size = 0;
ssh->private = NULL;
(void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa));
ksp = kstat_create(name, 0, "txgs", "misc",
KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL);
ssh->kstat = ksp;
if (ksp) {
ksp->ks_lock = &ssh->lock;
ksp->ks_data = NULL;
ksp->ks_private = spa;
ksp->ks_update = spa_txg_history_update;
kstat_set_raw_ops(ksp, spa_txg_history_headers,
spa_txg_history_data, spa_txg_history_addr);
kstat_install(ksp);
}
}
static void
spa_txg_history_destroy(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
spa_txg_history_t *sth;
kstat_t *ksp;
ksp = ssh->kstat;
if (ksp)
kstat_delete(ksp);
mutex_enter(&ssh->lock);
while ((sth = list_remove_head(&ssh->list))) {
ssh->size--;
kmem_free(sth, sizeof (spa_txg_history_t));
}
ASSERT3U(ssh->size, ==, 0);
list_destroy(&ssh->list);
mutex_exit(&ssh->lock);
mutex_destroy(&ssh->lock);
}
/*
* Add a new txg to historical record.
*/
void
spa_txg_history_add(spa_t *spa, uint64_t txg, hrtime_t birth_time)
{
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
spa_txg_history_t *sth, *rm;
if (zfs_txg_history == 0 && ssh->size == 0)
return;
sth = kmem_zalloc(sizeof (spa_txg_history_t), KM_SLEEP);
sth->txg = txg;
sth->state = TXG_STATE_OPEN;
sth->times[TXG_STATE_BIRTH] = birth_time;
mutex_enter(&ssh->lock);
list_insert_head(&ssh->list, sth);
ssh->size++;
while (ssh->size > zfs_txg_history) {
ssh->size--;
rm = list_remove_tail(&ssh->list);
kmem_free(rm, sizeof (spa_txg_history_t));
}
mutex_exit(&ssh->lock);
}
/*
* Set txg state completion time and increment current state.
*/
int
spa_txg_history_set(spa_t *spa, uint64_t txg, txg_state_t completed_state,
hrtime_t completed_time)
{
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
spa_txg_history_t *sth;
int error = ENOENT;
if (zfs_txg_history == 0)
return (0);
mutex_enter(&ssh->lock);
for (sth = list_head(&ssh->list); sth != NULL;
sth = list_next(&ssh->list, sth)) {
if (sth->txg == txg) {
sth->times[completed_state] = completed_time;
sth->state++;
error = 0;
break;
}
}
mutex_exit(&ssh->lock);
return (error);
}
/*
* Set txg IO stats.
*/
int
spa_txg_history_set_io(spa_t *spa, uint64_t txg, uint64_t nread,
uint64_t nwritten, uint64_t reads, uint64_t writes, uint64_t ndirty)
{
spa_stats_history_t *ssh = &spa->spa_stats.txg_history;
spa_txg_history_t *sth;
int error = ENOENT;
if (zfs_txg_history == 0)
return (0);
mutex_enter(&ssh->lock);
for (sth = list_head(&ssh->list); sth != NULL;
sth = list_next(&ssh->list, sth)) {
if (sth->txg == txg) {
sth->nread = nread;
sth->nwritten = nwritten;
sth->reads = reads;
sth->writes = writes;
sth->ndirty = ndirty;
error = 0;
break;
}
}
mutex_exit(&ssh->lock);
return (error);
}
/*
* ==========================================================================
* SPA TX Assign Histogram Routines
* ==========================================================================
*/
/*
* Tx statistics - Information exported regarding dmu_tx_assign time.
*/
/*
* When the kstat is written zero all buckets. When the kstat is read
* count the number of trailing buckets set to zero and update ks_ndata
* such that they are not output.
*/
static int
spa_tx_assign_update(kstat_t *ksp, int rw)
{
spa_t *spa = ksp->ks_private;
spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram;
int i;
if (rw == KSTAT_WRITE) {
for (i = 0; i < ssh->count; i++)
((kstat_named_t *)ssh->private)[i].value.ui64 = 0;
}
for (i = ssh->count; i > 0; i--)
if (((kstat_named_t *)ssh->private)[i-1].value.ui64 != 0)
break;
ksp->ks_ndata = i;
ksp->ks_data_size = i * sizeof (kstat_named_t);
return (0);
}
static void
spa_tx_assign_init(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram;
char name[KSTAT_STRLEN];
kstat_named_t *ks;
kstat_t *ksp;
int i;
mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL);
ssh->count = 42; /* power of two buckets for 1ns to 2,199s */
ssh->size = ssh->count * sizeof (kstat_named_t);
ssh->private = kmem_alloc(ssh->size, KM_SLEEP);
(void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa));
for (i = 0; i < ssh->count; i++) {
ks = &((kstat_named_t *)ssh->private)[i];
ks->data_type = KSTAT_DATA_UINT64;
ks->value.ui64 = 0;
(void) snprintf(ks->name, KSTAT_STRLEN, "%llu ns",
(u_longlong_t)1 << i);
}
ksp = kstat_create(name, 0, "dmu_tx_assign", "misc",
KSTAT_TYPE_NAMED, 0, KSTAT_FLAG_VIRTUAL);
ssh->kstat = ksp;
if (ksp) {
ksp->ks_lock = &ssh->lock;
ksp->ks_data = ssh->private;
ksp->ks_ndata = ssh->count;
ksp->ks_data_size = ssh->size;
ksp->ks_private = spa;
ksp->ks_update = spa_tx_assign_update;
kstat_install(ksp);
}
}
static void
spa_tx_assign_destroy(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram;
kstat_t *ksp;
ksp = ssh->kstat;
if (ksp)
kstat_delete(ksp);
kmem_free(ssh->private, ssh->size);
mutex_destroy(&ssh->lock);
}
void
spa_tx_assign_add_nsecs(spa_t *spa, uint64_t nsecs)
{
spa_stats_history_t *ssh = &spa->spa_stats.tx_assign_histogram;
uint64_t idx = 0;
while (((1ULL << idx) < nsecs) && (idx < ssh->size - 1))
idx++;
atomic_inc_64(&((kstat_named_t *)ssh->private)[idx].value.ui64);
}
/*
* ==========================================================================
* SPA IO History Routines
* ==========================================================================
*/
static int
spa_io_history_update(kstat_t *ksp, int rw)
{
if (rw == KSTAT_WRITE)
memset(ksp->ks_data, 0, ksp->ks_data_size);
return (0);
}
static void
spa_io_history_init(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.io_history;
char name[KSTAT_STRLEN];
kstat_t *ksp;
mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL);
(void) snprintf(name, KSTAT_STRLEN, "zfs/%s", spa_name(spa));
ksp = kstat_create(name, 0, "io", "disk", KSTAT_TYPE_IO, 1, 0);
ssh->kstat = ksp;
if (ksp) {
ksp->ks_lock = &ssh->lock;
ksp->ks_private = spa;
ksp->ks_update = spa_io_history_update;
kstat_install(ksp);
}
}
static void
spa_io_history_destroy(spa_t *spa)
{
spa_stats_history_t *ssh = &spa->spa_stats.io_history;
if (ssh->kstat)
kstat_delete(ssh->kstat);
mutex_destroy(&ssh->lock);
}
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
void
spa_stats_init(spa_t *spa)
{
spa_read_history_init(spa);
spa_txg_history_init(spa);
spa_tx_assign_init(spa);
spa_io_history_init(spa);
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
}
void
spa_stats_destroy(spa_t *spa)
{
spa_tx_assign_destroy(spa);
spa_txg_history_destroy(spa);
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
spa_read_history_destroy(spa);
spa_io_history_destroy(spa);
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
}
#if defined(_KERNEL) && defined(HAVE_SPL)
module_param(zfs_read_history, int, 0644);
MODULE_PARM_DESC(zfs_read_history, "Historic statistics for the last N reads");
module_param(zfs_read_history_hits, int, 0644);
MODULE_PARM_DESC(zfs_read_history_hits, "Include cache hits in read history");
module_param(zfs_txg_history, int, 0644);
MODULE_PARM_DESC(zfs_txg_history, "Historic statistics for the last N txgs");
Add visibility in to arc_read This change is an attempt to add visibility into the arc_read calls occurring on a system, in real time. To do this, a list was added to the in memory SPA data structure for a pool, with each element on the list corresponding to a call to arc_read. These entries are then exported through the kstat interface, which can then be interpreted in userspace. For each arc_read call, the following information is exported: * A unique identifier (uint64_t) * The time the entry was added to the list (hrtime_t) (*not* wall clock time; relative to the other entries on the list) * The objset ID (uint64_t) * The object number (uint64_t) * The indirection level (uint64_t) * The block ID (uint64_t) * The name of the function originating the arc_read call (char[24]) * The arc_flags from the arc_read call (uint32_t) * The PID of the reading thread (pid_t) * The command or name of thread originating read (char[16]) From this exported information one can see, in real time, exactly what is being read, what function is generating the read, and whether or not the read was found to be already cached. There is still some work to be done, but this should serve as a good starting point. Specifically, dbuf_read's are not accounted for in the currently exported information. Thus, a follow up patch should probably be added to export these calls that never call into arc_read (they only hit the dbuf hash table). In addition, it might be nice to create a utility similar to "arcstat.py" to digest the exported information and display it in a more readable format. Or perhaps, log the information and allow for it to be "replayed" at a later time. Signed-off-by: Prakash Surya <surya1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-09-06 23:09:05 +00:00
#endif