Re: 2.6.20-rc6 ramdisk problem

[Robert Hancock <hancockr@shaw.ca>]

Thomas Gleixner wrote:
> On Wed, 2007-01-31 at 17:54 -0600, Robert Hancock wrote:
>> I'm not sure if there's an inherent max ramdisk size limit, however I 
>> should point out that in most cases, using a tmpfs or ramfs file system 
>> is better than old-style ramdisks. Those filesystems return unused 
>> memory to the kernel (ramdisks statically allocate the entire space) and 
>> also avoid the filesystem overhead of ramdisks (the files are mapped 
>> into pagecache directly).
> 
> This is not a question of what's better or not. 
> 
> Michal stepped into a real life problem:
> 
> 1. ramdisk gets created in the first place w/o problems
> 2. formatting the same ramdisk succeeds
> 3. trying to use it fails
> 
> So either #1 or #2 should have failed in the first place. Failing in #3
> is definitely a BUG in #1 or #2.
> 
> How does your advise help to fix that BUG ? Ignoring it by using
> something else ?

Yes, there is likely a bug here of some sort. However, that doesn't 
change the fact that ramdisks are sub-optimal for most uses.

-- 
Robert Hancock      Saskatoon, SK, Canada
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