Kore no longer passes the accept lock to the "next in line"
worker but instead all workers will attempt to grab the lock
if they can.
Also remember if we had the lock previous iteration of the
event loop and don't constantly disable/enable the accepting sockets.
Makes Kore scale even better across multiple cpu's.
Tasks are now assigned to available threads instead
of a global task list.
You can now pass messages between your page handler
and the created task using the kore_task_channel_*
functions.
Only one task per time can be assigned to a request
but I feel this is probably a bad design choice.
Preferably we'd want to be able to start tasks
regardless of being in a page handler or not,
this not only ads flexibility but seems like
a better choice overall as it opens a lot more
possibilities about how tasks can be used.
Has support for full async pgsql queries. Most of the logic
is hidden behind a KORE_PGSQL() macro allowing you to insert
these pgsql calls in your page handlers without blocking the
kore worker while the query is going off.
There is place for improvement here, and perhaps KORE_PGSQL won't
stay as I feel this might overcomplicate things instead of making
them simpler as I thought it would.
- Introduce own memory management system on top of malloc to keep track
of all our allocations and free's. Later we should introduce a pooling
mechanism for fixed size allocations (http_request comes to mind).
- Introduce ssl_cipher in configuration.
Memory usage is kind of high right now, but it seems its OpenSSL
doing it rather then Kore.
Instead of waiting until one worker is filled up on connections
the workers find the next lowest loaded worker and will hand
over the lock to them instead. This will cause a nicer spread of load.
Instead of running one accept per event loop, we attempt to accept
as many as worker_max_connections allows.
Refactor net sending/recv code a bit.
new connections and which ones will not be notified for it.
Fixes the thundering herd problem, and nicely spreads out load between
all the workers equally. A configuration option (workers_max_connections)
is available to tweak how many connections a worker will have before
giving up the accept lock.
Two ways are added to this commit for access locking:
- Locking via semaphores.
- Locking via GCC's builtin atomic methods.
The default is running with semaphores disabled (OpenBSD cannot do
sem_init() with pshared set to 1, which is required).
If you want to use semaphores add KORE_USE_SEMAPHORES to CFLAGS,
and -lpthread to LDFLAGS in the Makefile.
Other fixes:
- BSD: add a timeout to kevent().
- Merge kore_worker_wait together, linux knows waitpid() as well.
- Send the correct SIGQUIT signal to workers instead of SIGINT.
- Fix kore_time_ms().
- Log fatal worker messages in syslog.
- Refactor code even more.
- Do not free our own kore_worker structure.
