<div dir="ltr">Hi,<br><br>Here you go...<br><br>--- old 2009-09-08 17:47:41.000000000 +0300<br>+++ new 2009-09-08 17:47:31.000000000 +0300<br>@@ -1,38 +1,45 @@<br>-tune2fs 1.40-WIP (14-Nov-2006)<br>-Filesystem volume name: /<br>
+tune2fs 1.41.3 (12-Oct-2008)<br>+Filesystem volume name: <none><br> Last mounted on: <not available><br>-Filesystem UUID: 5a1d4aa2-a4e8-48a5-b80d-03dbcebb2a4c<br>+Filesystem UUID: 466838ce-735c-4523-9941-ecab400e22c4<br>
Filesystem magic number: 0xEF53<br> Filesystem revision #: 1 (dynamic)<br>-Filesystem features: has_journal filetype needs_recovery sparse_super<br>-Filesystem flags: signed directory hash <br>+Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery sparse_super large_file<br>
+Filesystem flags: signed_directory_hash <br> Default mount options: (none)<br> Filesystem state: clean<br> Errors behavior: Continue<br> Filesystem OS type: Linux<br>-Inode count: 9584640<br>
-Block count: 19153488<br>-Reserved block count: 957674<br>-Free blocks: 16844413<br>-Free inodes: 9328387<br>+Inode count: 9601024<br>+Block count: 38399358<br>
+Reserved block count: 1919967<br>+Free blocks: 37358729<br>+Free inodes: 9551984<br> First block: 0<br> Block size: 4096<br> Fragment size: 4096<br>+Reserved GDT blocks: 1014<br>
Blocks per group: 32768<br> Fragments per group: 32768<br>-Inodes per group: 16384<br>+Inodes per group: 8192<br> Inode blocks per group: 512<br>-Last mount time: Sun Jun 14 14:00:14 2009<br>
-Last write time: Sun Jun 14 14:00:14 2009<br>-Mount count: 17<br>-Maximum mount count: 30<br>-Last checked: Sun Jan 20 17:04:43 2008<br>-Check interval: 0 (<none>)<br>
+Filesystem created: Wed Aug 12 14:18:23 2009<br>+Last mount time: Tue Sep 8 09:08:05 2009<br>+Last write time: Tue Sep 8 09:08:05 2009<br>+Mount count: 3<br>+Maximum mount count: 20<br>
+Last checked: Fri Sep 4 18:46:20 2009<br>+Check interval: 15552000 (6 months)<br>+Next check after: Wed Mar 3 17:46:20 2010<br> Reserved blocks uid: 0 (user root)<br> Reserved blocks gid: 0 (group root)<br>
First inode: 11<br>-Inode size: 128<br>+Inode size: 256<br>+Required extra isize: 28<br>+Desired extra isize: 28<br> Journal inode: 8<br>-First orphan inode: 2097564<br>
+First orphan inode: 3777224<br>+Default directory hash: half_md4<br>+Directory Hash Seed: 8998eea4-7d31-437f-bf0b-a12c3dc853ab<br> Journal backup: inode blocks<br><br><br><div class="gmail_quote">2009/9/8 Arie Skliarouk <span dir="ltr"><<a href="mailto:skliarie@gmail.com">skliarie@gmail.com</a>></span><br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div dir="ltr">Hi,<br><br>Interesting riddle...<div class="im"><br><br>2009/9/8 Noam Rathaus <span dir="ltr"><<a href="mailto:noamr@beyondsecurity.com" target="_blank">noamr@beyondsecurity.com</a>></span><br>
</div><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div dir="ltr">The most notable difference is the read time on files (new HD)<div class="im"><br>0.047210 read(7, " <= 0)\n {\n $numLimit = 10;\n }\n\n "..., 4096)<br><br>Instead of (old HW)<br>
0.001462 read(6, "owItem = $1;\n\n my $RowItems = $s"..., 4096) = 4096<br><br>That is 40 times slower (it is the same file being opened)<br></div></div></blockquote><div><br>What is the filesystem used on the machines? Do they have similar mount flags (no_atime or such)?<br>
If both are ext2/3, compare "tune2fs -l /dev/sda1" on them.<br>Try to mount both filesystems using noatime and compare timings then.<br><br>Full disk might affect fragmentation or placement of the files and thus require long seeks. As atime needs to be updated (or journal log), buffering in memory would not help.<br>
Test write speed of the disks.<br> <br>--<br><font color="#888888">Arie<br></font></div><div><div></div><div class="h5"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div dir="ltr"><br>I have no idea why there is such a difference<br>
<br>hdparm on the old:<br>
hdparm -t /dev/sda<br><br>/dev/sda:<br> Timing buffered disk reads: 190 MB in 3.02 seconds = 62.87 MB/sec<br><br>hdparm on the new:<br># hdparm -t /dev/sda<br><br>/dev/sda:<br> Timing buffered disk reads: 314 MB in 3.01 seconds = 104.22 MB/sec<br>
<br><div class="gmail_quote">On Tue, Sep 8, 2009 at 3:02 PM, Noam Meltzer <span dir="ltr"><<a href="mailto:tsnoam@gmail.com" target="_blank">tsnoam@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div dir="ltr">Did you try to check with strace ?<br><br><div class="gmail_quote"><div>2009/9/8 Noam Rathaus <span dir="ltr"><<a href="mailto:noamr@beyondsecurity.com" target="_blank">noamr@beyondsecurity.com</a>></span><br>
</div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div><div></div><div>
<div dir="ltr">Hi,<div><div></div><div><br><br>I have two machines, their hardware is not identical, but their installation is.<br><br>One is a 3 years old DELL server, while the other is a 1 year old server.<br>
<br>One is running 2.6.26-2-686 while the other 2.6.30-1-686<br>
<br>What I am seeing is slow startup - emphasis on startup, the code works fast once its running - of perl scripts<br><br>Even the smallest perl script such as this:<br>===<br>#!/usr/bin/perl<br><br>use lib '/usr/local/MySystem/lib';<br>
<br>use DB;<br><br>===<br><br>Take 7 seconds to start, in comparison to 0.030secods<br><br>If I don't use the "use DB;" which my package<br><br>It loads fast<br><br>I am trying to figure out why, I checked the HD speeds via hdparam, the newer server is 1.5 times faster 103MB/sec<br>
<br>I tried to see what libraries were being used, used strace, but I can't see something "big" that is causing the delay.<br><br>The "use DB;" can be replaced with any other "custom" library package I wrote, they all take 2-7 seconds to load, while on the other machine it takes negligible time<br>
<br>Does someone have a "thread" to cling to?<br><br>Thanks,<br>Noam Rathaus<br></div></div></div>
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