[lkml]   [2001]   [Nov]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Special Kernel Modification
From said:
> > Mounting it synchronous will disable caching in the VM.
> Who told
> you that? Synchronous mounting turns off write buffering. Even with
> "-o sync" writes will still end up in the page cache, they'll just be
> commited immediately.

Ummm, how about O_DIRECT instead of O_SYNC (or maybe as well, my googling
hasn't been clear on whether O_DIRECT bypasses the cache on writes as well)?

All IO bypasses the virtual machine cache, so there's no multiple caching.

> Er, it will be shared in the host's context, but each VM will still
> have their own copy in the page cache. This is no better than a
> COW'ed block device

Nope. You O_DIRECT here as well.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:12    [W:0.097 / U:4.968 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site