From cdb6adaf33f9219288f89364a0ab76812c5bff66 Mon Sep 17 00:00:00 2001 From: Christian Ambach Date: Fri, 14 Jan 2011 13:55:28 +0100 Subject: [PATCH] improve timing issue detections the original "Time jumped" messages are too coarse to interpret exactly what was going wrong inside of CTDB. This patch removes the original logs and adds two other logs that differentiate between the time it took to work on an event and the time it took to get the next event. --- lib/tevent/tevent.c | 15 ----------- lib/tevent/tevent_epoll.c | 2 ++ lib/tevent/tevent_select.c | 2 ++ lib/tevent/tevent_standard.c | 2 ++ lib/tevent/tevent_util.c | 51 ++++++++++++++++++++++++++++++++++++ lib/tevent/tevent_util.h | 4 +++ 6 files changed, 61 insertions(+), 15 deletions(-) diff --git a/lib/tevent/tevent.c b/lib/tevent/tevent.c index 2f6e591b..88ae01c4 100644 --- a/lib/tevent/tevent.c +++ b/lib/tevent/tevent.c @@ -590,8 +590,6 @@ extern pid_t ctdbd_pid; int tevent_common_loop_wait(struct tevent_context *ev, const char *location) { - static time_t t=0; - time_t new_t; /* * loop as long as we have events pending @@ -608,19 +606,6 @@ int tevent_common_loop_wait(struct tevent_context *ev, ret, strerror(errno)); return ret; } - if (getpid() == ctdbd_pid) { - new_t=time(NULL); - if (t != 0) { - if (t > new_t) { - tevent_debug(ev, TEVENT_DEBUG_FATAL, __location__ " ERROR Time skipped backward by %d seconds\n", (int)(t-new_t)); - } - /* We assume here that we get at least one event every 3 seconds */ - if (new_t > (t+3)) { - tevent_debug(ev, TEVENT_DEBUG_FATAL, __location__ " ERROR Time jumped forward by %d seconds\n", (int)(new_t-t)); - } - } - t=new_t; - } } tevent_debug(ev, TEVENT_DEBUG_WARNING, diff --git a/lib/tevent/tevent_epoll.c b/lib/tevent/tevent_epoll.c index 3abb0e63..e443f9fa 100644 --- a/lib/tevent/tevent_epoll.c +++ b/lib/tevent/tevent_epoll.c @@ -250,7 +250,9 @@ static int epoll_event_loop(struct epoll_event_context *epoll_ev, struct timeval return 0; } + tevent_before_wait(epoll_ev->ev); ret = epoll_wait(epoll_ev->epoll_fd, events, MAXEVENTS, timeout); + tevent_after_wait(epoll_ev->ev); if (ret == -1 && errno == EINTR && epoll_ev->ev->signal_events) { if (tevent_common_check_signal(epoll_ev->ev)) { diff --git a/lib/tevent/tevent_select.c b/lib/tevent/tevent_select.c index 128a7d6b..f25ce05a 100644 --- a/lib/tevent/tevent_select.c +++ b/lib/tevent/tevent_select.c @@ -157,7 +157,9 @@ static int select_event_loop_select(struct select_event_context *select_ev, stru return 0; } + tevent_before_wait(select_ev->ev); selrtn = select(select_ev->maxfd+1, &r_fds, &w_fds, NULL, tvalp); + tevent_after_wait(select_ev->ev); if (selrtn == -1 && errno == EINTR && select_ev->ev->signal_events) { diff --git a/lib/tevent/tevent_standard.c b/lib/tevent/tevent_standard.c index 3f2d6d5b..abebbd8d 100644 --- a/lib/tevent/tevent_standard.c +++ b/lib/tevent/tevent_standard.c @@ -261,7 +261,9 @@ static int epoll_event_loop(struct std_event_context *std_ev, struct timeval *tv return 0; } + tevent_before_wait(std_ev->ev); ret = epoll_wait(std_ev->epoll_fd, events, MAXEVENTS, timeout); + tevent_after_wait(std_ev->ev); if (ret == -1 && errno == EINTR && std_ev->ev->signal_events) { if (tevent_common_check_signal(std_ev->ev)) { diff --git a/lib/tevent/tevent_util.c b/lib/tevent/tevent_util.c index f78cd8f7..28c9da34 100644 --- a/lib/tevent/tevent_util.c +++ b/lib/tevent/tevent_util.c @@ -88,3 +88,54 @@ int ev_set_blocking(int fd, bool set) return fcntl( fd, F_SETFL, val); #undef FLAG_TO_SET } + +static struct timeval tevent_before_wait_ts; +static struct timeval tevent_after_wait_ts; + +/* + * measure the time difference between multiple arrivals + * to the point where we wait for new events to come in + * + * allows to measure how long it takes to work on a + * event + */ +void tevent_before_wait(struct event_context *ev) { + + struct timeval diff; + struct timeval now = tevent_timeval_current(); + + if (!tevent_timeval_is_zero(&tevent_after_wait_ts)) { + diff = tevent_timeval_until(&tevent_after_wait_ts, &now); + if (diff.tv_sec > 3) { + tevent_debug(ev, TEVENT_DEBUG_FATAL, __location__ + " Handling event took %d seconds!", + (int) diff.tv_sec); + } + } + + tevent_before_wait_ts = tevent_timeval_current(); + +} + +/* + * measure how long the select()/epoll() call took + * + * allows to measure how long we are waiting for new events + */ +void tevent_after_wait(struct event_context *ev) { + + struct timeval diff; + struct timeval now = tevent_timeval_current(); + + if (!tevent_timeval_is_zero(&tevent_before_wait_ts)) { + diff = tevent_timeval_until(&tevent_before_wait_ts, &now); + if (diff.tv_sec > 3) { + tevent_debug(ev, TEVENT_DEBUG_FATAL, __location__ + " No event for %d seconds!", + (int) diff.tv_sec); + } + } + + tevent_after_wait_ts = tevent_timeval_current(); + +} diff --git a/lib/tevent/tevent_util.h b/lib/tevent/tevent_util.h index 46a4506d..2852e9f2 100644 --- a/lib/tevent/tevent_util.h +++ b/lib/tevent/tevent_util.h @@ -184,6 +184,10 @@ const char **ev_str_list_add(const char **list, const char *s); int ev_set_blocking(int fd, bool set); size_t ev_str_list_length(const char **list); +void tevent_before_wait(struct event_context *ev); +void tevent_after_wait(struct event_context *ev); + + /* Defined here so we can build against older talloc versions that don't * have this define yet. */ #ifndef TALLOC_FREE -- 2.34.1