fix(profiler): don't double compress non-delta profiles#3918
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Our non-delta heap, block, and mutex profiles are getting double-compressed. That is, they are gzip-compressed, and if you decompress them then you get another gzip-compressed blob, which is in turn a compressed pprof file. This is due to a bug introduced by #3529. In that PR we reworked our compression logic in order to support re-compression (into zstd in particular). We incorrectly decided whether a given profile type is a delta profile by just checking whether there are delta values for the profile, without checking whether delta profiling is actually enabled. As a result, when delta profiling is disabled we use the delta profling _enabled_ logic, where we assume the input data is uncomprossed and then gzip-compress it.
BenchmarksBenchmark execution time: 2025-08-26 20:39:42 Comparing candidate commit 62c127f in PR branch Found 0 performance improvements and 0 performance regressions! Performance is the same for 24 metrics, 0 unstable metrics. |
nsrip-dd
marked this pull request as ready for review
August 26, 2025 20:30
felixge
approved these changes
Aug 27, 2025
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Our non-delta heap, block, and mutex profiles are getting
double-compressed. That is, they are gzip-compressed, and if you
decompress them then you get another gzip-compressed blob, which is in
turn a compressed pprof file.
This is due to a bug introduced by #3529. In that PR we reworked our
compression logic in order to support re-compression (into zstd in
particular). We incorrectly decided whether a given profile type is a
delta profile by just checking whether there are delta values for the
profile type, without checking whether delta profiling is actually enabled.
As a result, when delta profiling is disabled we use the delta profling
enabled logic, where we assume the input data is uncomprossed and then
gzip-compress it.