Hi Otto, On Sun, Jan 5, 2025 at 1:43 AM Otto Kekäläinen <otto@kekalainen.net> wrote:
It is probably just easier that you push email me a patch or share me an url where I can download it, and I can do the testing for you.
I just created https://github.com/MariaDB/server/pull/3732 with the following of 2 commits, which are currently also available in the 10.11-MDEV-35785 branch: https://github.com/MariaDB/server/pull/3732/commits/10f0f36457852075af5ce784... https://github.com/MariaDB/server/pull/3732/commits/4268d64587b10e4b8dce2b50...
Thanks for the clarification. With this additional context I understand now that https://github.com/MariaDB/server/commit/3f9f5ca48e6be55613926964314f550c8ca... re-implemented that function in MariaDB and thus the pmem library can be removed everywhere, but that MariaDB continues to use pmem kernel API in 10.11+.
The whole point of PMEM is that there is no kernel API, other than the MAP_SYNC flag of the mmap() system call. All that a durable log write takes is writing back some cache lines, which can be initiated with an unprivileged instruction, without any context switch between user and kernel mode being necessary. I'm looking forward to your test results on RISC-V and LoongArch. Marko -- Marko Mäkelä, Lead Developer InnoDB MariaDB plc