Convert SharedFileSet->refcnt to an atomic variable.
Currently, this variable is an int protected by a spinlock. By
converting it to an atomic variable, we can remove the spinlock.
Detaching becomes an atomic subtract, and attaching becomes a
compare-and-exchange loop, since it must not resurrect a fileset
whose reference count has already reached zero.
Reviewed-by: Zsolt Parragi <zsolt.parragi@percona.com>
Tested-by: solai v <solai.cdac@gmail.com>
Discussion: https://postgr.es/m/alAJeRRzehDjLaF1%40nathan
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/09a579abaca86bcd85ebc49b247d2ec58bdc6d3b
Modified Files
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src/backend/storage/file/sharedfileset.c | 33 ++++++++++++++------------------
src/include/storage/sharedfileset.h | 5 ++---
2 files changed, 16 insertions(+), 22 deletions(-)
