freebsd-skq/usr.bin/netstat/mbuf.c
glebius aaa09777e1 New sendfile(2) syscall. A joint effort of NGINX and Netflix from 2013 and
up to now.

The new sendfile is the code that Netflix uses to send their multiple tens
of gigabits of data per second. The new implementation features asynchronous
I/O, when I/O operations are launched, but not awaited to be complete. An
explanation of why such behavior is beneficial compared to old one is
going to be too long for a commit message, so we will skip it here.

Additional features of new syscall are extra flags, which provide an
application more control over data sent. The SF_NOCACHE flag tells
kernel that data shouldn't be cached after it was sent. The SF_READAHEAD()
macro allows to specify readahead size in pages.

The new syscalls is a drop in replacement. No modifications are required
to applications. One can take nginx binary for stable/10 and run it
successfully on head. Although SF_NODISKIO lost its original sense, as now
sendfile doesn't block, and now means something completely different (tm),
using the new sendfile the old way is absolutely safe.

Celebrates:	Netflix global launch!
Sponsored by:	Nginx, Inc.
Sponsored by:	Netflix
Relnotes:	yes
2016-01-08 20:34:57 +00:00

360 lines
13 KiB
C

/*-
* Copyright (c) 1983, 1988, 1993
* The Regents of the University of California.
* Copyright (c) 2005 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)mbuf.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/sf_buf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <err.h>
#include <kvm.h>
#include <memstat.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <libxo/xo.h>
#include "netstat.h"
/*
* Print mbuf statistics.
*/
void
mbpr(void *kvmd, u_long mbaddr)
{
struct memory_type_list *mtlp;
struct memory_type *mtp;
uintmax_t mbuf_count, mbuf_bytes, mbuf_free, mbuf_failures, mbuf_size;
uintmax_t mbuf_sleeps;
uintmax_t cluster_count, cluster_limit, cluster_free;
uintmax_t cluster_failures, cluster_size, cluster_sleeps;
uintmax_t packet_count, packet_bytes, packet_free, packet_failures;
uintmax_t packet_sleeps;
uintmax_t tag_bytes;
uintmax_t jumbop_count, jumbop_limit, jumbop_free;
uintmax_t jumbop_failures, jumbop_sleeps, jumbop_size;
uintmax_t jumbo9_count, jumbo9_limit, jumbo9_free;
uintmax_t jumbo9_failures, jumbo9_sleeps, jumbo9_size;
uintmax_t jumbo16_count, jumbo16_limit, jumbo16_free;
uintmax_t jumbo16_failures, jumbo16_sleeps, jumbo16_size;
uintmax_t bytes_inuse, bytes_incache, bytes_total;
int nsfbufs, nsfbufspeak, nsfbufsused;
struct sfstat sfstat;
size_t mlen;
int error;
mtlp = memstat_mtl_alloc();
if (mtlp == NULL) {
xo_warn("memstat_mtl_alloc");
return;
}
/*
* Use memstat_*_all() because some mbuf-related memory is in uma(9),
* and some malloc(9).
*/
if (live) {
if (memstat_sysctl_all(mtlp, 0) < 0) {
xo_warnx("memstat_sysctl_all: %s",
memstat_strerror(memstat_mtl_geterror(mtlp)));
goto out;
}
} else {
if (memstat_kvm_all(mtlp, kvmd) < 0) {
error = memstat_mtl_geterror(mtlp);
if (error == MEMSTAT_ERROR_KVM)
xo_warnx("memstat_kvm_all: %s",
kvm_geterr(kvmd));
else
xo_warnx("memstat_kvm_all: %s",
memstat_strerror(error));
goto out;
}
}
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found", MBUF_MEM_NAME);
goto out;
}
mbuf_count = memstat_get_count(mtp);
mbuf_bytes = memstat_get_bytes(mtp);
mbuf_free = memstat_get_free(mtp);
mbuf_failures = memstat_get_failures(mtp);
mbuf_sleeps = memstat_get_sleeps(mtp);
mbuf_size = memstat_get_size(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_PACKET_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found",
MBUF_PACKET_MEM_NAME);
goto out;
}
packet_count = memstat_get_count(mtp);
packet_bytes = memstat_get_bytes(mtp);
packet_free = memstat_get_free(mtp);
packet_sleeps = memstat_get_sleeps(mtp);
packet_failures = memstat_get_failures(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_CLUSTER_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found",
MBUF_CLUSTER_MEM_NAME);
goto out;
}
cluster_count = memstat_get_count(mtp);
cluster_limit = memstat_get_countlimit(mtp);
cluster_free = memstat_get_free(mtp);
cluster_failures = memstat_get_failures(mtp);
cluster_sleeps = memstat_get_sleeps(mtp);
cluster_size = memstat_get_size(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_MALLOC, MBUF_TAG_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: malloc type %s not found",
MBUF_TAG_MEM_NAME);
goto out;
}
tag_bytes = memstat_get_bytes(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_JUMBOP_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found",
MBUF_JUMBOP_MEM_NAME);
goto out;
}
jumbop_count = memstat_get_count(mtp);
jumbop_limit = memstat_get_countlimit(mtp);
jumbop_free = memstat_get_free(mtp);
jumbop_failures = memstat_get_failures(mtp);
jumbop_sleeps = memstat_get_sleeps(mtp);
jumbop_size = memstat_get_size(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_JUMBO9_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found",
MBUF_JUMBO9_MEM_NAME);
goto out;
}
jumbo9_count = memstat_get_count(mtp);
jumbo9_limit = memstat_get_countlimit(mtp);
jumbo9_free = memstat_get_free(mtp);
jumbo9_failures = memstat_get_failures(mtp);
jumbo9_sleeps = memstat_get_sleeps(mtp);
jumbo9_size = memstat_get_size(mtp);
mtp = memstat_mtl_find(mtlp, ALLOCATOR_UMA, MBUF_JUMBO16_MEM_NAME);
if (mtp == NULL) {
xo_warnx("memstat_mtl_find: zone %s not found",
MBUF_JUMBO16_MEM_NAME);
goto out;
}
jumbo16_count = memstat_get_count(mtp);
jumbo16_limit = memstat_get_countlimit(mtp);
jumbo16_free = memstat_get_free(mtp);
jumbo16_failures = memstat_get_failures(mtp);
jumbo16_sleeps = memstat_get_sleeps(mtp);
jumbo16_size = memstat_get_size(mtp);
xo_open_container("mbuf-statistics");
xo_emit("{:mbuf-current/%ju}/{:mbuf-cache/%ju}/{:mbuf-total/%ju} "
"{N:mbufs in use (current\\/cache\\/total)}\n",
mbuf_count + packet_count, mbuf_free + packet_free,
mbuf_count + packet_count + mbuf_free + packet_free);
xo_emit("{:cluster-current/%ju}/{:cluster-cache/%ju}/"
"{:cluster-total/%ju}/{:cluster-max/%ju} "
"{N:mbuf clusters in use (current\\/cache\\/total\\/max)}\n",
cluster_count - packet_free, cluster_free + packet_free,
cluster_count + cluster_free, cluster_limit);
xo_emit("{:packet-count/%ju}/{:packet-free/%ju} "
"{N:mbuf+clusters out of packet secondary zone in use "
"(current\\/cache)}\n",
packet_count, packet_free);
xo_emit("{:jumbo-count/%ju}/{:jumbo-cache/%ju}/{:jumbo-total/%ju}/"
"{:jumbo-max/%ju} {:jumbo-page-size/%ju}{U:k} {N:(page size)} "
"{N:jumbo clusters in use (current\\/cache\\/total\\/max)}\n",
jumbop_count, jumbop_free, jumbop_count + jumbop_free,
jumbop_limit, jumbop_size / 1024);
xo_emit("{:jumbo9-count/%ju}/{:jumbo9-cache/%ju}/"
"{:jumbo9-total/%ju}/{:jumbo9-max/%ju} "
"{N:9k jumbo clusters in use (current\\/cache\\/total\\/max)}\n",
jumbo9_count, jumbo9_free, jumbo9_count + jumbo9_free,
jumbo9_limit);
xo_emit("{:jumbo16-count/%ju}/{:jumbo16-cache/%ju}/"
"{:jumbo16-total/%ju}/{:jumbo16-limit/%ju} "
"{N:16k jumbo clusters in use (current\\/cache\\/total\\/max)}\n",
jumbo16_count, jumbo16_free, jumbo16_count + jumbo16_free,
jumbo16_limit);
#if 0
xo_emit("{:tag-count/%ju} {N:mbuf tags in use}\n", tag_count);
#endif
/*-
* Calculate in-use bytes as:
* - straight mbuf memory
* - mbuf memory in packets
* - the clusters attached to packets
* - and the rest of the non-packet-attached clusters.
* - m_tag memory
* This avoids counting the clusters attached to packets in the cache.
* This currently excludes sf_buf space.
*/
bytes_inuse =
mbuf_bytes + /* straight mbuf memory */
packet_bytes + /* mbufs in packets */
(packet_count * cluster_size) + /* clusters in packets */
/* other clusters */
((cluster_count - packet_count - packet_free) * cluster_size) +
tag_bytes +
(jumbop_count * jumbop_size) + /* jumbo clusters */
(jumbo9_count * jumbo9_size) +
(jumbo16_count * jumbo16_size);
/*
* Calculate in-cache bytes as:
* - cached straught mbufs
* - cached packet mbufs
* - cached packet clusters
* - cached straight clusters
* This currently excludes sf_buf space.
*/
bytes_incache =
(mbuf_free * mbuf_size) + /* straight free mbufs */
(packet_free * mbuf_size) + /* mbufs in free packets */
(packet_free * cluster_size) + /* clusters in free packets */
(cluster_free * cluster_size) + /* free clusters */
(jumbop_free * jumbop_size) + /* jumbo clusters */
(jumbo9_free * jumbo9_size) +
(jumbo16_free * jumbo16_size);
/*
* Total is bytes in use + bytes in cache. This doesn't take into
* account various other misc data structures, overhead, etc, but
* gives the user something useful despite that.
*/
bytes_total = bytes_inuse + bytes_incache;
xo_emit("{:bytes-in-use/%ju}{U:K}/{:bytes-in-cache/%ju}{U:K}/"
"{:bytes-total/%ju}{U:K} "
"{N:bytes allocated to network (current\\/cache\\/total)}\n",
bytes_inuse / 1024, bytes_incache / 1024, bytes_total / 1024);
xo_emit("{:mbuf-failures/%ju}/{:cluster-failures/%ju}/"
"{:packet-failures/%ju} {N:requests for mbufs denied "
"(mbufs\\/clusters\\/mbuf+clusters)}\n",
mbuf_failures, cluster_failures, packet_failures);
xo_emit("{:mbuf-sleeps/%ju}/{:cluster-sleeps/%ju}/{:packet-sleeps/%ju} "
"{N:requests for mbufs delayed "
"(mbufs\\/clusters\\/mbuf+clusters)}\n",
mbuf_sleeps, cluster_sleeps, packet_sleeps);
xo_emit("{:jumbop-sleeps/%ju}/{:jumbo9-sleeps/%ju}/"
"{:jumbo16-sleeps/%ju} {N:/requests for jumbo clusters delayed "
"(%juk\\/9k\\/16k)}\n",
jumbop_sleeps, jumbo9_sleeps, jumbo16_sleeps, jumbop_size / 1024);
xo_emit("{:jumbop-failures/%ju}/{:jumbo9-failures/%ju}/"
"{:jumbo16-failures/%ju} {N:/requests for jumbo clusters denied "
"(%juk\\/9k\\/16k)}\n",
jumbop_failures, jumbo9_failures, jumbo16_failures,
jumbop_size / 1024);
mlen = sizeof(nsfbufs);
if (live &&
sysctlbyname("kern.ipc.nsfbufs", &nsfbufs, &mlen, NULL, 0) == 0 &&
sysctlbyname("kern.ipc.nsfbufsused", &nsfbufsused, &mlen,
NULL, 0) == 0 &&
sysctlbyname("kern.ipc.nsfbufspeak", &nsfbufspeak, &mlen,
NULL, 0) == 0)
xo_emit("{:nsfbufs-current/%d}/{:nsfbufs-peak/%d}/"
"{:nsfbufs/%d} "
"{N:sfbufs in use (current\\/peak\\/max)}\n",
nsfbufsused, nsfbufspeak, nsfbufs);
if (fetch_stats("kern.ipc.sfstat", mbaddr, &sfstat, sizeof(sfstat),
kread_counters) != 0)
goto out;
xo_emit("{:sendfile-syscalls/%ju} {N:sendfile syscalls}\n",
(uintmax_t)sfstat.sf_syscalls);
xo_emit("{:sendfile-no-io/%ju} "
"{N:sendfile syscalls completed without I\\/O request}\n",
(uintmax_t)sfstat.sf_noiocnt);
xo_emit("{:sendfile-io-count/%ju} "
"{N:requests for I\\/O initiated by sendfile}\n",
(uintmax_t)sfstat.sf_iocnt);
xo_emit("{:sendfile-pages-sent/%ju} "
"{N:pages read by sendfile as part of a request}\n",
(uintmax_t)sfstat.sf_pages_read);
xo_emit("{:sendfile-pages-valid/%ju} "
"{N:pages were valid at time of a sendfile request}\n",
(uintmax_t)sfstat.sf_pages_valid);
xo_emit("{:sendfile-requested-readahead/%ju} "
"{N:pages were requested for read ahead by applications}\n",
(uintmax_t)sfstat.sf_rhpages_requested);
xo_emit("{:sendfile-readahead/%ju} "
"{N:pages were read ahead by sendfile}\n",
(uintmax_t)sfstat.sf_rhpages_read);
xo_emit("{:sendfile-busy-encounters/%ju} "
"{N:times sendfile encountered an already busy page}\n",
(uintmax_t)sfstat.sf_busy);
xo_emit("{:sfbufs-alloc-failed/%ju} {N:requests for sfbufs denied}\n",
(uintmax_t)sfstat.sf_allocfail);
xo_emit("{:sfbufs-alloc-wait/%ju} {N:requests for sfbufs delayed}\n",
(uintmax_t)sfstat.sf_allocwait);
out:
xo_close_container("mbuf-statistics");
memstat_mtl_free(mtlp);
}