Fix GC profiling timing #214
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We were recording GC profile timestamps inside the VM postponed job that flushes temporary information. The postponed job could be run much later than the sample was actually taken, so this commit records a timestamp in the signal handler when there is a GC event. It only records one time stamp, so if there are multiple GC events in a row, we have to assume that the total duration spent in GC starts from the first time stamp and extends until the timestamp of the next non-GC sample. In other words, we don't record a correct timestamp for each GC sample, only the first one.
jhawthorn
approved these changes
Jul 11, 2023
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We were recording GC profile timestamps inside the VM postponed job that flushes temporary information. The postponed job could be run much later than the sample was actually taken, so this commit records a timestamp in the signal handler when there is a GC event.
It only records one time stamp, so if there are multiple GC events in a row, we have to assume that the total duration spent in GC starts from the first time stamp and extends until the timestamp of the next non-GC sample. In other words, we don't record a correct timestamp for each GC sample, only the first one.