Subject: Re: bug#9500: [PATCH]: use posix_fallocate where supported

From: Pádraig Brady <[email-masked]>
Date: Tue, 29 Nov 2011 12:59:01 +0000

On 11/25/2011 10:59 AM, Pádraig Brady wrote:
> On 11/25/2011 10:13 AM, Pádraig Brady wrote:
> 
>> Hmm, one of your points above got me thinking.
>> Might fallocate() fail to allocate an extent with ENOSPC,
>> but there could be fragmented space available to write()?
>> That would scupper benefit (2) above :(
>> I'll ask [email-masked]
> 
> And the response from there is that fallocate() will
> check the free blocks first, and then try to allocate
> as a contiguous extent, but that part is not guaranteed.
> So we still get benefit (2).

However that thread has continued, and it
was mentioned that benefit (1) might actually
be detrimental, at least for small files.

http://thread.gmane.org/gmane.linux.file-systems/59092

le sigh,
Pádraig.