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Matt Graham wrote:
<blockquote cite="mid:957mLsuo56162S12.1229717756@cmsweb12.cms.usa.net"
type="cite">
<pre wrap="">From: Lars Ellenberg <a class="moz-txt-link-rfc2396E" href="mailto:lars.ellenberg@linbit.com"><lars.ellenberg@linbit.com></a>
</pre>
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">So when building the initial LVM and mkfs.ext3, what are some
options that I should be using on an array that will start at
2TB and grow to about 10TB as I add more disks?
</pre>
</blockquote>
<pre wrap="">I may be wrong, but I think on intel/amd ext3 is still limited
to < 8TiB ?
</pre>
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<pre wrap=""><!---->
Docs say the max filesystem size for ext23 on the x86 is 16T with
4K blocks. I don't know how much this has been tested or used in
the real world, since arrays that large are still out of my price
range.
</pre>
<blockquote type="cite">
<pre wrap="">ever seen e2fsck on a multi terabyte device?
</pre>
</blockquote>
<pre wrap=""><!---->
It takes a while, which is why he's using ext3. You'd run into
the same problems with any filesystem when things go south,
really. Don't worry, it'll all be fixed in ext4 (currently in
alpha).
</pre>
<blockquote type="cite">
<pre wrap="">why not go for XFS? seems to be a better choice for device
sizes in that range.
</pre>
</blockquote>
<pre wrap=""><!---->
Maybe he wants his data to still be there if there's a power
failure :-)
</pre>
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And there is another point, recently I tested areca cards with RAID5
and LVM. I put DRBD on top of the LVM and then XFS.<br>
With XFS and high I/O load the machines gives me kernel panic, I had
tested it about for a week, to understand where was the problem.<br>
<br>
- XFS directly on LVM gives no problems at all.<br>
- Ext3 directly on LVM gives no problems at all.<br>
- XFS on top of drbd, and drbd on top LVM, gives kernel panic with drbd
8.0.X and with 8.2.X.<br>
- Ext3 on top of drbd, and drbd on top LVM, gives no problems at all.<br>
<br>
Sorry I cant show you any kernel panic, but when I took XFS from the
way, everything works, but I know it's not a problem of XFS since XFS
works fine directly on top of LVM.<br>
<br>
Everything I tested, was on top of Centos 5, with the latest updates.<br>
<br>
XFS it's incredibly faster then ext3, but ext3 it's widely tested and
proved so far, so for this more strange setups with drbd on the game,
don't use XFS.<br>
<br>
Good Luck,<br>
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