Re: missing madvise functionality

Andi Kleen
2007-04-03T20:09:39Z

> It might, a bit. Both mmap() and mprotect() currently take mmap_sem() for
> writing. If we're careful, we could probably arrange for MADV_ULRICH to
> take it for reading, which will help a little bit, hopefully.

The cache line bounces would be still there. Not sure that would help MySQL
all that much.

Besides if the down_write is the real problem one could convert
the code for all cases over to optimistic locking assuming most calls
don't merge.

-Andi