Mercurial > hg > nginx-quic
view auto/os/darwin @ 7281:bd6563e81cea
Limit req: improved handling of negative times.
Negative times can appear since workers only update time on an event
loop iteration start. If a worker was blocked for a long time during
an event loop iteration, it is possible that another worker already
updated the time stored in the node. As such, time since last update
of the node (ms) will be negative.
Previous code used ngx_abs(ms) in the calculations. That is, negative
times were effectively treated as positive ones. As a result, it was
not possible to maintain high request rates, where the same node can be
updated multiple times from during an event loop iteration.
In particular, this affected setups with many SSL handshakes, see
http://mailman.nginx.org/pipermail/nginx/2018-May/056291.html.
Fix is to only update the last update time stored in the node if the
new time is larger than previously stored one. If a future time is
stored in the node, we preserve this time as is.
To prevent breaking things on platforms without monotonic time available
if system time is updated backwards, a safety limit of 60 seconds is
used. If the time stored in the node is more than 60 seconds in the future,
we assume that the time was changed backwards and update lr->last
to the current time.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 30 May 2018 15:40:34 +0300 |
parents | 9fb994513776 |
children |
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# Copyright (C) Igor Sysoev # Copyright (C) Nginx, Inc. have=NGX_DARWIN . auto/have_headers CORE_INCS="$UNIX_INCS" CORE_DEPS="$UNIX_DEPS $DARWIN_DEPS" CORE_SRCS="$UNIX_SRCS $DARWIN_SRCS" ngx_spacer=' ' MAIN_LINK= MODULE_LINK="-shared -Wl,-undefined,dynamic_lookup" CC_AUX_FLAGS="$CC_AUX_FLAGS -D__APPLE_USE_RFC_3542" # kqueue echo " + kqueue found" have=NGX_HAVE_KQUEUE . auto/have have=NGX_HAVE_CLEAR_EVENT . auto/have EVENT_MODULES="$EVENT_MODULES $KQUEUE_MODULE" CORE_SRCS="$CORE_SRCS $KQUEUE_SRCS" EVENT_FOUND=YES NGX_KQUEUE_CHECKED=YES ngx_feature="kqueue's EVFILT_TIMER" ngx_feature_name="NGX_HAVE_TIMER_EVENT" ngx_feature_run=yes ngx_feature_incs="#include <sys/event.h> #include <sys/time.h>" ngx_feature_path= ngx_feature_libs= ngx_feature_test="int kq; struct kevent kev; struct timespec ts; if ((kq = kqueue()) == -1) return 1; kev.ident = 0; kev.filter = EVFILT_TIMER; kev.flags = EV_ADD|EV_ENABLE; kev.fflags = 0; kev.data = 1000; kev.udata = 0; ts.tv_sec = 0; ts.tv_nsec = 0; if (kevent(kq, &kev, 1, &kev, 1, &ts) == -1) return 1; if (kev.flags & EV_ERROR) return 1;" . auto/feature ngx_feature="Darwin 64-bit kqueue millisecond timeout bug" ngx_feature_name=NGX_DARWIN_KEVENT_BUG ngx_feature_run=bug ngx_feature_incs="#include <sys/event.h> #include <sys/time.h>" ngx_feature_path= ngx_feature_libs= ngx_feature_test="int kq; struct kevent kev; struct timespec ts; struct timeval tv, tv0; kq = kqueue(); ts.tv_sec = 0; ts.tv_nsec = 999000000; gettimeofday(&tv, 0); kevent(kq, NULL, 0, &kev, 1, &ts); gettimeofday(&tv0, 0); timersub(&tv0, &tv, &tv); if (tv.tv_sec * 1000000 + tv.tv_usec < 900000) return 1;" . auto/feature # sendfile() ngx_feature="sendfile()" ngx_feature_name="NGX_HAVE_SENDFILE" ngx_feature_run=yes ngx_feature_incs="#include <sys/types.h> #include <sys/socket.h> #include <sys/uio.h> #include <sys/errno.h>" ngx_feature_path= ngx_feature_libs= ngx_feature_test="int s = 0, fd = 1; off_t n; off_t off = 0; n = sendfile(s, fd, off, &n, NULL, 0); if (n == -1 && errno == ENOSYS) return 1" . auto/feature if [ $ngx_found = yes ]; then CORE_SRCS="$CORE_SRCS $DARWIN_SENDFILE_SRCS" fi ngx_feature="atomic(3)" ngx_feature_name=NGX_DARWIN_ATOMIC ngx_feature_run=no ngx_feature_incs="#include <libkern/OSAtomic.h>" ngx_feature_path= ngx_feature_libs= ngx_feature_test="int32_t lock = 0; if (!OSAtomicCompareAndSwap32Barrier(0, 1, &lock)) return 1" . auto/feature