initialize all the data. This is huge waste of time and resources if
there were no writes yet, as there is no real data to synchronize.
Optimize this by sending "virgin" argument to secondary, which gives it a hint
that synchronization is not needed.
In the common case (where noth nodes are configured at the same time) instead
of synchronizing everything, we don't synchronize at all.
MFC after: 1 week
This way the primary process inherits signal mask from the main process,
which fixes a race where signal is delivered to the primary process before
configuring signal mask.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
while the main process sends control message to the worker process, but worker
process hasn't started control thread yet, because it waits for reply from the
main process.
The fix is to start the control thread before sending any events.
Reported and fix suggested by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
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
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
