From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from n1.cetrtapot.si ([212.30.80.17]) by canuck.infradead.org with esmtp (Exim 4.52 #1 (Red Hat Linux)) id 1EKYM8-0001vx-8s for linux-mtd@lists.infradead.org; Wed, 28 Sep 2005 05:36:08 -0400 Received: from localhost (localhost.dmz.cetrtapot.si [127.0.0.1]) by n1.cetrtapot.si (Postfix) with ESMTP id BEAE7BB5E for ; Wed, 28 Sep 2005 11:35:58 +0200 (CEST) Received: from n1.cetrtapot.si ([127.0.0.1]) by localhost (n1.dmz.cetrtapot.si [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 87248-08 for ; Wed, 28 Sep 2005 11:35:50 +0200 (CEST) Received: from [192.1.1.75] (unknown [192.168.66.2]) by n1.cetrtapot.si (Postfix) with ESMTP id 7A2D5BB5A for ; Wed, 28 Sep 2005 11:35:50 +0200 (CEST) Message-ID: <433A640D.6030200@cetrtapot.si> Date: Wed, 28 Sep 2005 11:36:13 +0200 From: "hinko.kocevar@cetrtapot.si" MIME-Version: 1.0 To: Linux MTD Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Great jffs2 speedup List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, We started using new CVS code that provides EBS and fragtree method. Below are some measurements of mount times for old and new setup. NAND partitions size tested were: flash4 - 4Mb flash5 - 12Mb flash6 - 16Mb OLD setup uses ~April 2005 MTD code, 2.6.11 kernel, no EBS and produces following: Mounting flash4 clean partition [1] real 0m 0.83s user 0m 0.01s sys 0m 0.83s -- -- -- -- -- -- -- -- -- -- Mounting flash4 dirty partition [2] real 0m 8.37s user 0m 0.01s sys 0m 8.35s -- -- -- -- -- -- -- -- -- -- Mounting flash5 clean partition real 0m 2.70s user 0m 0.02s sys 0m 2.38s -- -- -- -- -- -- -- -- -- -- Mounting flash5 dirty partition real 0m 26.42s user 0m 0.01s sys 0m 26.40s -- -- -- -- -- -- -- -- -- -- Mounting flash6 clean partition real 0m 3.29s user 0m 0.02s sys 0m 3.16s -- -- -- -- -- -- -- -- -- -- Mounting flash6 dirty partition real 0m 35.81s user 0m 0.01s sys 0m 35.77s -- -- -- -- -- -- -- -- -- -- On new setup - using yesterdays MTD CVS and 2.6.12 kernel with EBS enabled: Mounting flash4 clean partition [1] real 0m 3.75s user 0m 0.02s sys 0m 1.17s -- -- -- -- -- -- -- -- -- -- Mounting flash4 dirty partition [2] real 0m 0.75s user 0m 0.02s sys 0m 0.73s -- -- -- -- -- -- -- -- -- -- Mounting flash5 clean partition real 0m 3.55s user 0m 0.02s sys 0m 3.47s -- -- -- -- -- -- -- -- -- -- Mounting flash5 dirty partition real 0m 2.12s user 0m 0.03s sys 0m 2.08s -- -- -- -- -- -- -- -- -- -- Mounting flash6 clean partition real 0m 4.82s user 0m 0.01s sys 0m 4.63s -- -- -- -- -- -- -- -- -- -- Mounting flash6 dirty partition real 0m 2.82s user 0m 0.01s sys 0m 2.80s -- -- -- -- -- -- -- -- -- -- Compared to old setup this is GREAAAAAT improvment (if my mesurements are correct:). Great job! This holds true /only/ if partition is erased beforehand and then mounted, filled with files, umounted and mounted again to mesure mount time for dirty partition. Mounting jffs2 partition filled on old setup shows no performance improvement. We found sumtool utility in tools dir and if my understanding is correct it is used to convert jffs2 image with no EBS to jffs2 image with EBS. Is this the only way to upgrade 'old' jffs2 partitions already in place (on the nand flash) to use EBS? Thing is, we have several system up and running in the wild and would like to upgrade jffs2 partitions as-painless-as-possible, preferably without complete reflash of the systems. I've just ran sumtool on old raw 4Mb mtd char device (containing jffs2 fs) and it produced 4Mb image on the output. I figure, if I copy this image back to flash and test it with EBS supported kernel it should recognize it as new jffs2 image and mount it super-fast. I still need to erase the nand partition and gather enough ram for temporary EBS image on the system and so this could be a problem in our setup. regards, hinko [1] Mounting clean partition means that we erased the partition with flash_eraseall and then mounted it. mount time was measured with 'time'. [2] After cleaning up the partition, then creating, appending, erasing several small files on it, we umounted the partition and mounted it back. mount time was measured eith 'time'. All partitions contained 150 - 700 few kbytes sizes files and were ~80 % full when dirty.