From: root
Date: Thu, 22 Nov 2007 12:28:27 +0000 (+0000)
Subject: *** empty log message ***
X-Git-Tag: rel-1_3~32
X-Git-Url: https://git.llucax.com/software/libev.git/commitdiff_plain/54a57c74105dc818388cec05e6fc874cdbfebf7f?hp=99c0baac0b99f53c7a0bb4a0c5a8a10e8b97605f
*** empty log message ***
---
diff --git a/ev.3 b/ev.3
index 190f657..ab5e004 100644
--- a/ev.3
+++ b/ev.3
@@ -316,8 +316,9 @@ it's really slow, but it still scales very well (O(active_fds)).
.ie n .IP """EVMETHOD_ALL""" 4
.el .IP "\f(CWEVMETHOD_ALL\fR" 4
.IX Item "EVMETHOD_ALL"
-Try all backends (even potentially broken ones). Since this is a mask, you
-can do stuff like \f(CW\*(C`EVMETHOD_ALL & ~EVMETHOD_KQUEUE\*(C'\fR.
+Try all backends (even potentially broken ones that wouldn't be tried
+with \f(CW\*(C`EVFLAG_AUTO\*(C'\fR). Since this is a mask, you can do stuff such as
+\&\f(CW\*(C`EVMETHOD_ALL & ~EVMETHOD_KQUEUE\*(C'\fR.
.RE
.RS 4
.Sp
diff --git a/ev.c b/ev.c
index c6a0e97..88e3474 100644
--- a/ev.c
+++ b/ev.c
@@ -810,11 +810,20 @@ loop_init (EV_P_ unsigned int flags)
now_floor = mn_now;
rtmn_diff = ev_rt_now - mn_now;
- if (!(flags & EVFLAG_NOENV) && !enable_secure () && getenv ("LIBEV_FLAGS"))
+ if (!(flags & EVFLAG_NOENV)
+ && !enable_secure ()
+ && getenv ("LIBEV_FLAGS"))
flags = atoi (getenv ("LIBEV_FLAGS"));
- if (!(flags & 0x0000ffff))
- flags |= 0x0000ffff;
+ if (!(flags & EVMETHOD_ALL))
+ {
+ flags |= EVMETHOD_ALL;
+#if EV_USE_KQUEUE && !defined (__NetBSD__)
+ /* kqueue is borked on everything but netbsd apparently */
+ /* it usually doesn't work correctly on anything but sockets and pipes */
+ flags &= ~EVMETHOD_KQUEUE;
+#endif
+ }
method = 0;
#if EV_USE_PORT
diff --git a/ev.h b/ev.h
index 384df3e..c0da56b 100644
--- a/ev.h
+++ b/ev.h
@@ -242,6 +242,7 @@ union ev_any_watcher
#define EVMETHOD_KQUEUE 0x00000008 /* bsd */
#define EVMETHOD_DEVPOLL 0x00000010 /* solaris 8 */ /* NYI */
#define EVMETHOD_PORT 0x00000020 /* solaris 10 */
+#define EVMETHOD_ALL 0x0000ffff /* all methods, also future ones, or so */
/* flag bits */
#define EVFLAG_NOENV 0x01000000 /* do NOT consult environment */
diff --git a/ev.html b/ev.html
index 05a81f1..437179a 100644
--- a/ev.html
+++ b/ev.html
@@ -6,7 +6,7 @@
-
+
@@ -239,8 +239,9 @@ it's really slow, but it still scales very well (O(active_fds)).
EVMETHOD_ALL
-
Try all backends (even potentially broken ones). Since this is a mask, you
-can do stuff like EVMETHOD_ALL & ~EVMETHOD_KQUEUE.
+
Try all backends (even potentially broken ones that wouldn't be tried
+with EVFLAG_AUTO). Since this is a mask, you can do stuff such as
+EVMETHOD_ALL & ~EVMETHOD_KQUEUE.
diff --git a/ev.pod b/ev.pod
index 411fbb5..9845aff 100644
--- a/ev.pod
+++ b/ev.pod
@@ -147,24 +147,70 @@ override the flags completely if it is found in the environment. This is
useful to try out specific backends to test their performance, or to work
around bugs.
-=item C (portable select backend)
+=item C (value 1, portable select backend)
-=item C (poll backend, available everywhere except on windows)
+This is your standard select(2) backend. Not I standard, as
+libev tries to roll its own fd_set with no limits on the number of fds,
+but if that fails, expect a fairly low limit on the number of fds when
+using this backend. It doesn't scale too well (O(highest_fd)), but its usually
+the fastest backend for a low number of fds.
-=item C (linux only)
+=item C (value 2, poll backend, available everywhere except on windows)
-=item C (some bsds only)
+And this is your standard poll(2) backend. It's more complicated than
+select, but handles sparse fds better and has no artificial limit on the
+number of fds you can use (except it will slow down considerably with a
+lot of inactive fds). It scales similarly to select, i.e. O(total_fds).
-=item C (solaris 8 only)
+=item C (value 4, Linux)
-=item C (solaris 10 only)
+For few fds, this backend is a bit little slower than poll and select,
+but it scales phenomenally better. While poll and select usually scale like
+O(total_fds) where n is the total number of fds (or the highest fd), epoll scales
+either O(1) or O(active_fds).
-If one or more of these are ored into the flags value, then only these
-backends will be tried (in the reverse order as given here). If one are
-specified, any backend will do.
+While stopping and starting an I/O watcher in the same iteration will
+result in some caching, there is still a syscall per such incident
+(because the fd could point to a different file description now), so its
+best to avoid that. Also, dup()ed file descriptors might not work very
+well if you register events for both fds.
+
+=item C (value 8, most BSD clones)
+
+Kqueue deserves special mention, as at the time of this writing, it
+was broken on all BSDs except NetBSD (usually it doesn't work with
+anything but sockets and pipes, except on Darwin, where of course its
+completely useless). For this reason its not being "autodetected" unless
+you explicitly specify the flags (i.e. you don't use EVFLAG_AUTO).
+
+It scales in the same way as the epoll backend, but the interface to the
+kernel is more efficient (which says nothing about its actual speed, of
+course). While starting and stopping an I/O watcher does not cause an
+extra syscall as with epoll, it still adds up to four event changes per
+incident, so its best to avoid that.
+
+=item C (value 16, Solaris 8)
+
+This is not implemented yet (and might never be).
+
+=item C (value 32, Solaris 10)
+
+This uses the Solaris 10 port mechanism. As with everything on Solaris,
+it's really slow, but it still scales very well (O(active_fds)).
+
+=item C
+
+Try all backends (even potentially broken ones that wouldn't be tried
+with C). Since this is a mask, you can do stuff such as
+C.
=back
+If one or more of these are ored into the flags value, then only these
+backends will be tried (in the reverse order as given here). If none are
+specified, most compiled-in backend will be tried, usually in reverse
+order of their flag values :)
+
=item struct ev_loop *ev_loop_new (unsigned int flags)
Similar to C, but always creates a new event loop that is