From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yuriy Umanets Date: Tue, 19 Feb 2008 13:11:30 +0200 Subject: [Lustre-devel] storing SOM epoch in EA In-Reply-To: <200802191359.47379.vitaly@sun.com> References: <47BAA607.1000600@sun.com> <47BAAF3F.6030301@sun.com> <200802191359.47379.vitaly@sun.com> Message-ID: <47BAB962.8010901@sun.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org Vitaly Fertman wrote: >> hi! >> >> Can we use IAM for storing epoch? It is fast and does not have such >> strong size limitations. >> > there are no size limitations, EA can be stored in a separate > block, we just want to minimize IO. > > EA is separate block is evil. It makes things slow. >> We could make "epoch" index in mkfs time (like >> it is done for existing indexes now) and use object's fid as a key and >> epoch as value. >> > this looks like it will double IO/seeks for each inode. > > Well, it did not in cmd3 :) -- umka