X-Spam-Check-By:	sourceware.org
Date:	Tue, 16 Jan 2007 12:47:16 -0600
From:	Brian Ford <Brian DOT Ford AT FlightSafety DOT com>
Reply-To:	cygwin AT cygwin DOT com
To:	cygwin AT cygwin DOT com
Subject:	Re: Snapshot speed on managing files
In-Reply-To:	<20070113181859.GA5595@calimero.vinschen.de>
Message-ID:	<Pine.CYG.4.58.0701161221490.2732@PC1163-8460-XP.flightsafety.com>
References:	<62410 DOT 52144 DOT qm AT web25001 DOT mail DOT ukl DOT yahoo DOT com> <20070112102454 DOT GA8311 AT calimero DOT vinschen DOT de> <Pine DOT CYG DOT 4 DOT 58 DOT 0701121033010 DOT 320 AT PC1163-8460-XP DOT flightsafety DOT com> <20070113181859 DOT GA5595 AT calimero DOT vinschen DOT de>
MIME-Version:	1.0
X-IsSubscribed:	yes
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Unsubscribe:	<mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

On Sat, 13 Jan 2007, Corinna Vinschen wrote:
> On Jan 12 10:34, Brian Ford wrote:
> > On Fri, 12 Jan 2007, Corinna Vinschen wrote:
> > > Current CVS contains a change which is probably the cause for that.
> > > Before deleting a file, the file is moved to the recycle bin.
> >
> > Couldn't we make this conditional only if a "regular" delete fails because
> > the file is in use?  Would it then only penalize deletes of open files?
> >
> > (Incidentally, I've noticed this as well.)

Ok, I only noticed this anecdotally, not scientifically.  See below...

> Ok, next thing is taking the time with the current implementation
> which always moves the file to the bin:
>
>   $ ./deltest.sh
>   Creating files... Ok.
>   Deleting files ...
>   real    0m2.546s
>   user    0m0.233s
>   sys     0m0.578s

With this test case, I'm in your league:

$ ./deltest.sh
Creating files... Ok.
Deleting files ...
real    0m2.828s
user    0m0.296s
sys     0m1.531s

I'm also running "VirusScan Enterprise 8.0.0 On Access Scanner
Enabled" (corporate policy).

With On Access Scan disabled, I can reproduce the OP's result:

$ ./deltest.sh
Creating files... Ok.
Deleting files ...
real    1m45.333s
user    0m0.093s
sys     0m1.359s

A quick look via Filemon doesn't show where the time is going.  But since
I don't regularly run this way, I'm not that interested in pursuing this
further.

I regularly delete 100,000 files at a time under 1.5.18, and the rm return
is rather snappy.  About two weeks ago I was cleaning space of my drive
under a then current CVS build with On Access Scan enabled (before my 64k
I/O change, although I don't think that's relevant), and deleting a few
thousand files was very slow comparatively.  So, I presumed I had seen the
problem.

Since I can't duplicate this observation now, I'm sorry for the wasted
effort.

-- 
Brian Ford
Lead Realtime Software Engineer
VITAL - Visual Simulation Systems
FlightSafety International
the best safety device in any aircraft is a well-trained crew...



--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

- Raw text -