[Coco] 68 Micro Journal

[Steven Hirsch]

On Wed, 11 May 2011, gene heskett wrote:

> On Wednesday, May 11, 2011 11:00:14 AM Steven Hirsch did opine:
>
>> On Wed, 11 May 2011, gene heskett wrote:
>>> On Wednesday, May 11, 2011 10:39:31 AM Aaron Wolfe did opine:
>>>> both of these files are in the torrent here.  maybe someone else who
>>>> downloaded it can confirm that they have these files?
>>>
>>> Or, knowing that torrent pre-allocates the whole file, rechecks the
>>> target file on a restart, if their file is sparse, they should
>>> restart the torrent, causing it to recheck/compare, and fix any diffs
>>> between the src file and the local copy.
>>
>> Actually, not all bittorrent clients pre-allocate files by default.
>> This is particularly nasty when you download a DVD-sized ISO image with
>> sparse allocation.  Even on a fast disk system, reads of such a
>> fragmented image can be glacial.  The first time I ran into this, I
>> thought my RAID array had died and gone into limp-home mode.  Took a
>> while to figure out what was going on and turn on the "preallocate the
>> entire thing" option.
>
> There is quite likely that to contend with on some file systems.  You
> didn't say what OS & filesystem you are running, but if its that bad, I
> would change it forthwith.  Linux, with ext3 journaled, hasn't given me any
> trouble in that regard.

This was Linux, accessing an ext3 + journaling filesystem over NFS on a 
gigabit ethernet network.  It might be hitting NFSv3 at a weak point, 
since read speads are more typically > 50MB/sec.


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