<html><head><meta http-equiv="Content-Type" content="text/html charset=windows-1252"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><br><div><div>On Nov 10, 2014, at 11:26 PM, George R Goffe <<a href="mailto:grgoffe@yahoo.com">grgoffe@yahoo.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hi,<br><br>I have some large ext4 filesystems with large numbers of files in them and performance really sucks. After inactivity, a simple ls takes minutes to complete. I'm pretty sure the drive is now powering itself down due to this inactivity.<br><br><br>Are there tuning parameters that I could alter that would keep more of the filesystem meta data in memory? It looks like the data slowly migrates back to disk and as a result, takes minutes to fill back up enough to respond.<br><br>Regards and THANKS for your help and your time,</blockquote><br></div><div>It could be fragmentation or it could be non-optimal directory structure. When was the last fsck -f performed? It will optimize directories as needed, but can be forced with -D but I’d ask on the ext4 list before using it. And e4defrag -c can be used to get a fragmentation score, which can be run on a file or a directory.</div><div><br></div><div><a href="http://vger.kernel.org/vger-lists.html#linux-ext4">http://vger.kernel.org/vger-lists.html#linux-ext4</a></div><div><br></div><div><br></div><div>Chris Murphy</div></body></html>