[PATCH 0/2] upload-pack: reduce lock contention when writing packfile data

Hi,

this small patch series fixes some heavy lock contention when writing data from git-upload-pack(1) into pipes. This lock contention can be observed when having hundreds of git-upload-pack(1) processes active at the same time that write data into pipes at dozens of gigabits per second.

I have uploaded the flame graph that clearly shows the lock contention at [1].

Thanks!

Patrick

[1]: https://gitlab.com/gitlab-org/git/-/work_items/675

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Patrick Steinhardt (2):
      upload-pack: fix debug statement when flushing packfile data
      upload-pack: reduce lock contention when writing packfile data

 upload-pack.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- base-commit: 7b2bccb0d58d4f24705bf985de1f4612e4cf06e5 change-id: 20260227-pks-upload-pack-write-contention-435ce01f5fe9