`<div dir="ltr">Sorry, I should have given the requisite "yes, I know that this is a recipe for sadness, for I too have experienced said sadness". <div><br></div><div>That said, we've seen this kind of problem when there was a device in a vdev that was dying a slow death. There wouldn't necessarily be any sign, aside from insanely high service times on an individual device in the pool. From this, I assume that ZFS is still sensitive to variation in underlying drive performance. </div>
<div><br></div><div>Tobi, what do your drive service times look like?</div><div> -nld</div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Jan 21, 2014 at 7:58 AM, Dan McDonald <span dir="ltr"><<a href="mailto:danmcd@omniti.com" target="_blank">danmcd@omniti.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im"><br>
On Jan 21, 2014, at 7:21 AM, Narayan Desai <<a href="mailto:narayan.desai@gmail.com">narayan.desai@gmail.com</a>> wrote:<br>
<br>
> We've seen problems like this when we have a SATA drive in a SAS expander that is going out to lunch. Are there any drives showing errors in iostat -En? or any drive timeout messages in the ring buffer?<br>
<br>
</div>Generally speaking --> you use a SATA drive in a SAS expander at your own risk. I used to be at Nexenta, and they would not support customers who deployed SATA drives on SAS expanders. These days, the price delta between SAS and SATA (for enterprise) is small enough to be worth it for the headaches you avoid.<br>
<span class="HOEnZb"><font color="#888888"><br>
Dan<br>
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</font></span></blockquote></div><br></div>
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