- 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
to syslog if we run in background.
- Asserts in proto.c that method we want to call is implemented and remove
dummy methods from protocols implementation that are only there to abort
the program with nice message.
MFC after: 1 week
Accepting connections and handshaking in secondary is still done before
dropping privileges. It should be implemented by only accepting connections in
privileged main process and passing connection descriptors to the worker, but
is not implemented yet.
MFC after: 1 week
master process only and pass changes to the worker processes over control
socket. This removes access to global namespace in preparation for capsicum
sandboxing.
MFC after: 2 weeks
races - in this case a keepalive packet was send from wrong thread which
lead to connection dropping, because of corrupted packet.
Fix it by sending keepalive packets directly from the send thread.
As a bonus we now send keepalive packets only when connection is idle.
Submitted by: Mikolaj Golub <to.my.trociny@gmail.com>
MFC after: 3 days
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
I'm unable to reproduce the race described in comment anymore and also the
comment is incorrect - localfd represents local component from configuration
file, eg. /dev/da0 and not HAST provider.
Reported by: Mikolaj Golub <to.my.trociny@gmail.com>
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
This fixes various races and eliminates use of pthread* API in signal handler.
Pointed out by: kib
With help from: jilles
MFC after: 2 weeks
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
function to make code more readable.
- Be sure not to reconnect too often in case of signal delivery, etc.
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
- Load added resources.
- Stop and forget removed resources.
- Update modified resources in least intrusive way, ie. don't touch
/dev/hast/<name> unless path to local component or provider name were
modified.
Obtained from: Wheel Systems Sp. z o.o. http://www.wheelsystems.com
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
