Date: Fri, 25 Jun 2004 23:36:47 +0200
From: Pavel Machek <pavel@ucw.cz>
To: Amit Gud <gud@eth.net>
Cc: Alan <alan@clueserver.org>, Horst von Brand <vonbrand@inf.utfsm.cl>,
       "Fao, Sean" <Sean.Fao@dynextechnologies.com>,
       linux-kernel@vger.kernel.org
Subject: Re: Elastic Quota File System (EQFS)
Message-ID: <20040625213647.GA5907@elf.ucw.cz>
References: <004e01c45abd$35f8c0b0$b18309ca@home> <200406251444.i5PEiYpq008174@eeyore.valparaiso.cl> <20040625162537.GA6201@elf.ucw.cz> <1088181893.6558.12.camel@zontar.fnordora.org> <40DC625F.3010403@eth.net>
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Hi!

> >This sounds like a hack to get around a badly designed system with too
> I do believe that this system can be done in userspace, but it has its 
> own flaws then. Suppose theres a daemon, call it eqfsd. It forks parent 
> listens a char device, child watches the disk space usage. A kernel 
> module reports the file deletes, chowns to the char device, parent does 
> the needfull. Child 'periodically' checks that the threshold is not 
> reached. Here what can be done is suppose a user can transfer data with  
> say 5 Mbps speed to his account....then we can easily get the
> minimum 

I believe I can write data at 1GB/sec at common hardware (~RAM
speed). You'll either need a *lot* of free space, or very fast
polling, and it will still break when the daemon is swapped out, when
scheduler decides writer is more important etc.
								Pavel
-- 
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
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