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This is infrastructure to improve our async r/w result handling and latency. The pthreadpool signalling goes through a pipe. This has downsides: The main event loop has to go through a read on the pipe before it can ship the result. Also, it is not guaranteed by poll/epoll that the pthreadpool signal pipe is handled with top priority. When an async pread/pwrite has finished, we should immediately ship the result to the client, not waiting for anything else. This patch enables tevent_immediate structs as job signalling. This means a busy main tevent loop will handle the threaded job completion before any timed or file descriptor events. Opposite to Jeremy's tevent_thread_proxy this is done by a modification of the main event loop by looking at a linked list under a central mutex. Regarding performance: In a later commit I've created a test that does nothing but fire one immediate over and over again. If you add a phread_mutex_lock and unlock pair in the immediate handler, you lose roughly 25% of rounds per second, so it is measurable. It is questionable that will be measurable in the real world, but to counter concerns activation of immediates needs to go through a new struct tevent_threaded_context. Only if such a tevent_threaded_context exists for a tevent context, the main loop takes the hit to look at the mutex'ed list of finished jobs. This patch by design does not care about talloc hierarchies. The idea is that the main thread owning the tevent context creates a chunk of memory and prepares the tevent_immediate indication job completion. The main thread hands the memory chunk together with the immediate as a job description over to a helper thread. The helper thread does its job and upon completion calls tevent_threaded_schedule_immediate with the already-prepared immediate. From that point on memory ownership is again transferred to the main thread. Signed-off-by: Volker Lendecke <vl@samba.org> Reviewed-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Jeremy Allison <jra@samba.org>
compression - Various compression algorithms (MSZIP, lzxpress)
dnspython - Python module for working with DNS.
nss_wrapper - Wrapper for the user and group NSS API allowing the use
of other data sources.
popt - Command-line option parsing library
replace - Provides replacements for standard (POSIX, C99) functions
not provided by the host platform.
socket_wrapper - Wrapper library allowing TCP/IP traffic to be redirected
over Unix domain sockets.
subunit - Utilities and bindings for working with the Subunit test result
reporting protocol.
talloc - Hierarchical pool based memory allocator
tdb - Simple but fast key/value database library, supporting multiple writers
torture - Simple unit testing helper library