On Thu, 13 Jul 2017, Sean Paul <seanpaul@xxxxxxxxxxxx> wrote: > On Wed, Jul 12, 2017 at 02:12:24PM +0200, Daniel Vetter wrote: >> The problem is that we have a distributed cache - every committer has >> a copy. Which means even just a slight clock skew will make sure that >> a naive gc algorithm results in lots of thrashing around. >> >> To fix this add a huge hysteresis: Only add files newer than 1 day, >> and only remove them when older than 60 days. As long as people have >> reasonable accurate clocks on their machines this should work. >> >> A different problem is that we can't use filesystem timestamps (and >> hence can't use git rerere gc): When someone comes back from vacations >> and updates git rerere, all the files will have current timestamps, >> even when they've been pushed out weeks ago. To fix that, use the git >> log to judge old files to remove. Also, remove old files before adding >> new ones, to avoid confusion. >> >> Also, we need to teach the cp -r to preserve timestamps, otherwise >> this won't work. >> >> v2: Use git log to remove old files. >> >> v3: Remove the debug uncommenting (Sean). >> >> v4: Split out code movement and explain better what's going on (Jani). > > Yeah, much easier to digest with the split. > > Reviewed-by: Sean Paul <seanpaul@xxxxxxxxxxxx> I'll trust that and hope for the best. ;) BR, Jani. > >> >> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> >> --- >> dim | 10 ++++++++-- >> 1 file changed, 8 insertions(+), 2 deletions(-) >> >> diff --git a/dim b/dim >> index b788edd29653..79d616cbf354 100755 >> --- a/dim >> +++ b/dim >> @@ -513,9 +513,15 @@ function commit_rerere_cache >> >> git pull >& /dev/null >> rm $(rr_cache_dir)/rr-cache -Rf &> /dev/null || true >> - cp $(rr_cache_dir)/* rr-cache -r >> + cp $(rr_cache_dir)/* rr-cache -r --preserve=timestamps >> git add ./*.patch >& /dev/null || true >> - git add rr-cache/* > /dev/null >> + for file in $(git ls-files); do >> + if ! git log --since="60 days ago" --name-only -- $file | grep $file &> /dev/null; then >> + git rm $file &> /dev/null >> + echo deleting $file >> + fi >> + done >> + find rr-cache/ -ctime -1 -type f -print0 | xargs -0 git add > /dev/null >> git rm rr-cache/rr-cache &> /dev/null || true >> if git commit -m "$time: $integration_branch rerere cache update" >& /dev/null; then >> echo -n "New commit. " >> -- >> 2.13.2 >> >> _______________________________________________ >> dri-devel mailing list >> dri-devel@xxxxxxxxxxxxxxxxxxxxx >> https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
