From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.parrot.fr ([213.41.120.202]) by canuck.infradead.org with esmtps (Exim 4.63 #1 (Red Hat Linux)) id 1HJ6ES-0002by-Rn for linux-mtd@lists.infradead.org; Mon, 19 Feb 2007 05:59:00 -0500 Message-ID: <45D982F2.6050804@parrot.fr> Date: Mon, 19 Feb 2007 11:58:58 +0100 From: Matthieu CASTET MIME-Version: 1.0 To: David Woodhouse Subject: Re: jffs2 Erase Block Summary overhead References: <45D47C92.8080908@parrot.fr> <1171879537.7600.5.camel@pmac.infradead.org> In-Reply-To: <1171879537.7600.5.camel@pmac.infradead.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Cc: linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, David Woodhouse a écrit : > > There's a lot of redundant information in the summary; I think we could > halve it fairly easily. That would be great :) > I don't believe your 20% figure though -- that's > too high. You really can't rely on the output of df. > But the jffs2 layer say "no space left on device", so the it is really full. For more information on the test procedure, I fill the jffs2 filesystem with someting like : "i=0; while true; do dd if=/dev/urandom of=file.$i count=1024; i=$(($i+1));done" And I can create only 93 complete files, a incomplete file of 430 KB (and there should be 4 MB taken file others files). May be I am on a worse test case ? If I remove "Erase Block Summary", I can really fill the jffs2 up to 60MB [1] instead of 51MB. Thanks, Matthieu [1] # time mount /dev/mtdblock3 -t jffs2 /tmp/mnt/ ; time cat /tmp/mnt/root/file.1 > /dev/null ; du -sh /tmp/mnt; df real 0m 11.91s user 0m 0.00s sys 0m 11.91s real 0m 0.36s user 0m 0.01s sys 0m 0.35s 59.8M /tmp/mnt Filesystem Size Used Available Use% Mounted on /dev/ram0 4.4M 4.4M 0 100% / none 7.0M 16.0k 7.0M 0% /tmp none 7.0M 16.0k 7.0M 0% /tmp tmpfs 7.0M 16.0k 7.0M 0% /tmp /dev/mtdblock3 61.5M 60.9M 640.0k 99% /tmp/mnt