[Coco] 68 Micro Journal

Steven Hirsch snhirsch at gmail.com
Wed May 11 16:59:11 EDT 2011


On Wed, 11 May 2011, gene heskett wrote:

> On Wednesday, May 11, 2011 02:25:51 PM Steven Hirsch did opine:
>
>> 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.
>
> I would point a well sharpened finger at NFS3, I have never actually made
> it work as fast as a 125 kilobaud floppy here.  So if I need to send
> something to the buntu box running my milling machine, I use CIFS.

Hmm.  Well, as I said, typical throughput is about 50 MB/sec. on file 
read/write over my house LAN (gigabit).  I've never seen CIFS come 
anywhere near that, plus it munges file attributes and doesn't grok 
symlinks.

Never had any particular issues other than the one I mentioned.  My 
home directory is mounted over NFS as are all the areas where I do my 
work.

Steve


-- 




More information about the Coco mailing list