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| author | Max Kellermann <max.kellermann@ionos.com> | 2024-10-11 16:15:28 +0200 |
|---|---|---|
| committer | Max Kellermann <max.kellermann@ionos.com> | 2024-10-22 12:22:09 +0200 |
| commit | c2d192f527ba2ada103a3c3234f90c1e30118d98 (patch) | |
| tree | 9ed8a0dff534b5b69d978b38228d746901b8e30f | |
| parent | msg/async/Event{Poll,Epoll}: move timeout calculation to Timeout.h (diff) | |
| download | ceph-c2d192f527ba2ada103a3c3234f90c1e30118d98.tar.xz ceph-c2d192f527ba2ada103a3c3234f90c1e30118d98.zip | |
msg/async/Timeout: always round up
Currently, we always round down, which has a bad side effect: when a
timer comes closer, we have lots of early wakeups, and eventually
we'll run into a busy loop (timeout=0) when the timeout is less than
one millisecond; the process will remain this busy loop for one
millisecond, wasting lots of CPU time.
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
| -rw-r--r-- | src/msg/async/Timeout.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/src/msg/async/Timeout.h b/src/msg/async/Timeout.h index b47bcec8447..b8df1b40761 100644 --- a/src/msg/async/Timeout.h +++ b/src/msg/async/Timeout.h @@ -17,6 +17,8 @@ #ifndef CEPH_MSG_TIMEOUT_H #define CEPH_MSG_TIMEOUT_H +#include "include/intarith.h" // for div_round_up() + #include <time.h> // for struct timeval /** @@ -28,7 +30,8 @@ constexpr int timeout_to_milliseconds(const struct timeval &tv) noexcept { - return tv.tv_sec * 1000 + tv.tv_usec / 1000; + /* round up to the next millisecond so we don't wake up too early */ + return tv.tv_sec * 1000 + div_round_up(tv.tv_usec, 1000); } /** |