The idea is to drain the socket and do a single RocksDB WAL
write/fsync for all the write requests we have found.
The read requests are immediately executed. The reasoning here is
that currently write requests are _a lot_ slower than the read
requests because fsyncing takes ~500us on fsf1. In the future this
might change.
Since we're at it, we also use batch UDP syscalls in the CDC.
Fixes#119.
The goal here is to not have constant wakeups due to timeout. Do
not attempt to clean things up nicely before termination -- just
terminate instead. We can setup a proper termination system in
the future, I first want to see if this makes a difference.
Also, change xmon to use pipes for communication, so that it can
wait without timers as well.
Also, `write` directly for logging, so that we know the logs will
make it to the file after the logging call returns (since we now
do not have the chance to flush them afterwards).
This is to save on a ton of writes as jobs stat tons of files.
It would maybe be a bit cleaner to do it in the kmod, but this is
much quicker.
Thanks to @sgrusny for the good idea.
The `tuple` was for when I thought it'd be useful to leave slots
for each request, but we don't need this anymore, and now leading
up to #66 I want to be able to keep vectors of reqs/resps.
Fixes#32. This also involves some reworking of the block request machinery
to make it more robust and faster. The scrubbing is done assuming that
the overwhelming majority of block checking will go through.
This was triggered by a server failing hard (fsr13), without any
short term resolution (we've already replaced the mobo, we'll probably
replace the HBA). In this case GC should still run rather than
get stuck.
Fixes#29.
The additions to codegen are unrelated -- I was exploring a different
approach based on request equality and I decided to keep those
changes in since they might be useful anyhow.
Triggered by investigating
xmon: could not read message type: unexpected EOF, will reconnect
xmon: connected to xmon REDACTED
Undertaker: hard abort - running abort handlers
Uncaught exception thrown: SyscallException(Xmon.cpp@186, 9/EBADF=Bad file descriptor in void Xmon::run()): setsockopt
which caused crashes in shards/CDC.