Re: [PATCH, RFC] Use WRITE_SYNC in __block_write_full_page() if WBC_SYNC_ALL

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Jan 05 2009, Theodore Tso wrote:
> So long-term, I suspect the hueristic which makes sense is that in the
> case where there is an fsync() in progress, any writes which take
> place as a result of that fsync (which includes the journal records as
> well as ordered writes that are being forced out as a result of
> data=ordered and which block the fsync from returning), should get a
> hint which propagates down to the block layer that these writes *are*
> synchronous in that someone is waiting for them to complete.  They

If someone is waiting for them, they are by definition sync!

> shouldn't necessarily be prioritized ahead of other reads (unless they
> are readahead operations that couldn't be combined with reads that
> *are* synchronous that someone is waiting for completion), but they
> should be prioritized ahead of asynchronous writes.

And that is *exactly* what flagging the write as sync will do...

-- 
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux