issue: 4043235 TCP_USER_TIMER wrong RTO behavior #297
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AlexanderGrissik
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Removing bugged time calculations using x86-specific TSC to fix RTO issues. Replaced with platform calulcation. (clock_gettime) According to: https://gcc.gnu.org/legacy-ml/gcc-help/2019-07/msg00068.html This is more performant than previously considered chrono. Signed-off-by: Tomer Cabouly <[email protected]>
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Description
RTO calculations were producing wrong results over our incorrect TSC-based logic.
We were using /proc/cpuinfo which is not standardized, nor accurate:
htop-dev/htop#953
TSC is also x86 specific and considered unreliable in cases like dynamic frequency scaling.
Hence, we switch to platform clock which is more performant than chrono as can be seen here:
https://gcc.gnu.org/legacy-ml/gcc-help/2019-07/msg00068.html
What
Fix timers and RTO issues.
Why ?
Fix https://redmine.mellanox.com/issues/4043235.
Change type
What kind of change does this PR introduce?
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