kept dirty to reduce the number of on-disk metadata updates. The
sequence of operations is:
1) acquire the activemap lock;
2) update in-memory map;
3) if the list of keepdirty extents is changed, update on-disk metadata;
4) release the lock.
On-disk updates are not frequent in comparison with in-memory updates,
while require much more time. So situations are possible when one
thread is updating on-disk metadata and another one is waiting for the
activemap lock just to update the in-memory map.
Improve this by introducing additional, on-disk map lock: when
in-memory map is updated and it is detected that the on-disk map needs
update too, the on-disk map lock is acquired and the on-memory lock is
released before flushing the map.
Reported by: Yamagi Burmeister yamagi.org
Tested by: Yamagi Burmeister yamagi.org
Reviewed by: pjd
Approved by: re (marius)
MFC after: 2 weeks
why it will now be the default.
- Bump protocol version to 2 and add backward compatibility for version 1.
- Allow to specify hosts by kern.hostid as well (in addition to hostname and
kern.hostuuid) in configuration file.
Sponsored by: Panzura
Tested by: trociny
- old yacc(1) use to magicially append stdlib.h, while new one don't
- new yacc(1) do declare yyparse by itself, fix redundant declaration of
'yyparse'
Approved by: des (mentor)
reordering won't make the actual write to be committed before marking
the coresponding extent as dirty.
It can be disabled in configuration file.
If BIO_FLUSH is not supported by the underlying file system we log a warning
and never send BIO_FLUSH again to that GEOM provider.
MFC after: 3 days
requests as well as number of activemap updates.
Number of BIO_WRITEs and activemap updates are especially interesting, because
if those two are too close to each other, it means that your workload needs
bigger number of dirty extents. Activemap should be updated as rarely as
possible.
MFC after: 1 week
This way we know how to connect to secondary node when we are primary.
The same variable is used by the secondary node - it only accepts
connections from the address stored in 'remote' variable.
In cluster configurations it is common that each node has its individual
IP address and there is one addtional shared IP address which is assigned
to primary node. It seems it is possible that if the shared IP address is
from the same network as the individual IP address it might be choosen by
the kernel as a source address for connection with the secondary node.
Such connection will be rejected by secondary, as it doesn't come from
primary node individual IP.
Add 'source' variable that allows to specify source IP address we want to
bind to before connecting to the secondary node.
MFC after: 1 week
connection so the worker will exit if it does not receive packets from
the primary during this interval.
Reported by: Christian Vogt <Christian.Vogt@haw-hamburg.de>
Tested by: Christian Vogt <Christian.Vogt@haw-hamburg.de>
Approved by: pjd (mentor)
MFC after: 1 week
- HOLE - it simply turns all-zero blocks into few bytes header;
it is extremely fast, so it is turned on by default;
it is mostly intended to speed up initial synchronization
where we expect many zeros;
- LZF - very fast algorithm by Marc Alexander Lehmann, which shows
very decent compression ratio and has BSD license.
MFC after: 2 weeks
worker can ask the main privileged process to connect in worker's behalf
and then we can migrate descriptor using this socketpair to worker.
This is not really needed now, but will be needed once we start to use
capsicum for sandboxing.
MFC after: 1 week
- chrooting to /var/empty (user hast home directory),
- setting groups to 'hast' (user hast primary group),
- setting real group id, effective group id and saved group id to 'hast',
- setting real user id, effective user id and saved user id to 'hast'.
At the end verify that those operations where successfull.
MFC after: 1 week
limited to async-signal safe functions in the child process), move all hooks
execution to the main (non-threaded) process.
Do it by maintaining connection (socketpair) between child and parent
and sending events from the child to parent, so it can execute the hook.
This is step in right direction for others reasons too. For example there is
one less problem to drop privs in worker processes.
MFC after: 2 weeks
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
node failures quickly for HAST resources that are rarely modified.
Remove XXX from a comment now that the guard thread never sleeps infinitely.
MFC after: 2 weeks
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
- Don't exit on errors if not requested.
- Don't keep configuration in global variable, but allocate memory for
configuration.
- Call yyrestart() before yyparse() so that on error in configuration file
we will start from the begining next time and not from the place we left of.
MFC after: 1 month
secondary, which died between send(2) and recv(2). Do it by adding timeout
to recv(2) for primary incoming and outgoing sockets and secondary outgoing
socket.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
Tested by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
HAST allows to transparently store data on two physically separated machines
connected over the TCP/IP network. HAST works in Primary-Secondary
(Master-Backup, Master-Slave) configuration, which means that only one of the
cluster nodes can be active at any given time. Only Primary node is able to
handle I/O requests to HAST-managed devices. Currently HAST is limited to two
cluster nodes in total.
HAST operates on block level - it provides disk-like devices in /dev/hast/
directory for use by file systems and/or applications. Working on block level
makes it transparent for file systems and applications. There in no difference
between using HAST-provided device and raw disk, partition, etc. All of them
are just regular GEOM providers in FreeBSD.
For more information please consult hastd(8), hastctl(8) and hast.conf(5)
manual pages, as well as http://wiki.FreeBSD.org/HAST.
Sponsored by: FreeBSD Foundation
Sponsored by: OMCnet Internet Service GmbH
Sponsored by: TransIP BV
