fix: Return to read immediately after a successful read. #894
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Unit Test Results 1 files 27 suites 8m 40s ⏱️ For more details on these failures, see this check. Results for commit afd77e4. ♻️ This comment has been updated with latest results. |
Copying the filestream, now pipe, dgram, and socket streams return to read again immediately after a successful read, so that we don't wait. This is now obvious the problem in #685 and using the bandwidth-delay-product we can see that a 250ms pause between reads of 4096B and 128KiB matches the results seen. Before: ``` jaq% time ./mtail -logs - -progs examples/rsyncd.mtail < internal/mtail/testdata/rsyncd.log 0.01s user 0.01s system 7% cpu 0.264 total ``` After: ``` jaq% time ./mtail -logs - -progs examples/rsyncd.mtail < internal/mtail/testdata/rsyncd.log 0.01s user 0.03s system 102% cpu 0.041 total ``` Thanks to @rideliner for the hint.
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Copying the filestream, now pipe, dgram, and socket streams return to read
again immediately after a successful read, so that we don't wait.
This is now obviously the problem in #685 and using the bandwidth-delay-product
we can see that a 250ms pause between reads of 4096B and 128KiB matches the
results seen.
Before:
After:
Thanks to @rideliner for the hint.
Issue: #685