Benchmarks demonstrated that the idle timer handle approach didn't balance the
load quite fair enough, the majority of new connections still ended up in one
or two processes.
The new approach voluntarily gives up a scheduler timeslice by calling
nanosleep() with a one nanosecond timeout.
Why not sched_yield()? Because on Linux (and this is probably true for other
Unices as well), sched_yield() only yields if there are other processes running
on the same CPU.
nanosleep() on the other hand always forces the process to sleep, which gives
other processes a chance to accept our pending connections.
Adds initial libuv build/platform support for AIX. Builds work using gcc or the
IBM XL C compiler using its gxlc wrapper. Platform support is added for
uv_hrtime, uv_exepath, uv_get_free_memory, uv_get_total_memory, uv_loadavg,
uv_uptime, uv_cpu_info, uv_interface_addresses.
Implement a best effort approach to mitigating accept() EMFILE errors.
We have a spare file descriptor stashed away that we close to get below
the EMFILE limit. Next, we accept all pending connections and close them
immediately to signal the clients that we're overloaded - and we are, but
we still keep on trucking.
There is one caveat: it's not reliable in a multi-threaded environment.
The file descriptor limit is per process. Our party trick fails if another
thread opens a file or creates a socket in the time window between us
calling close() and accept().
Fixes#315.
kqueue(2) on osx doesn't work (emits EINVAL error) with specific fds
(i.e. /dev/tty, /dev/null, etc). When given such descriptors - start
select(2) watcher thread that will emit io events.
uv_fs_poll_t has an embedded uv_timer_t handle that got closed at a time when
the memory of the encapsulating handle might already have been deallocated.
Solve that by moving the poller's state into a structure that is allocated on
the heap and can be freed independently.
Readable tty handles need to be able to update the virtual window,
so if uv_tty_t is initialized with a console input fd, additionally
open the console output.
Formerly spawn errors would be reported as a message printed to the
process' stderr, to match unix behaviour. Unix has now been fixed to
be more sensible, so this hack can now be removed.
This also fixes a race condition that could occur when the user closes
a process handle before the exit callback has been made.
OS X has no public API for fdatasync. And as pointed out in `man fsync(2)`:
For applications that require tighter guarantees about the integrity of
their data, Mac OS X provides the F_FULLFSYNC fcntl. The F_FULLFSYNC
fcntl asks the drive to flush all buffered data to permanent storage.
Applications, such as databases, that require a strict ordering of writes
should use F_FULLFSYNC to ensure that their data is written in the order
they expect. Please see fcntl(2) for more detail.
The Sun Studio compiler did not define any of the symbols used to determine if
the system was a unix-like system or not causing it to include the windows
header.
