<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Jun 29, 2017 at 1:47 PM, Xie Changlong <span dir="ltr"><<a href="mailto:xiechanglong.d@gmail.com" target="_blank">xiechanglong.d@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi Krutika<br>
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Thanks for your quick response!<span class=""><br>
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在 6/29/2017 3:24 PM, Krutika Dhananjay 写道:<br>
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This is based on my high-level understanding of quota in gluster - supporting quota on sharded volumes will require us to make quota xlator account for shards residing under the hidden ".shard" directory per file and adding this to the quota-xattr representing aggregated consumed size on the parent directory of the original file.<br>
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This isn't hard to do. But at the moment we support sharding only for VM image store use case.<br>
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Why sharding only support VM large images? It's interesting. More, are there other limits for sharding usage? We want to reduce data reconstruction time with sharding, as you know it takes too long time to recover data with raid, and sharding is a good choice to us.<span class=""><br></span></blockquote><div><br></div><div>Yes, at the moment it "works" only for single-writer large file use cases - VM image store being the most common workload among them.<br></div><div>For a long time, one of the main complaints users had with gluster was slow heals for large size VM images. Our immediate focus at that time was to introduce shard for VM use case.<br><br></div><div>One of the main issues with multiple writers is ordering updates to the aggregated size xattr - which is a global metadata - following every file data modification operation, without compromising on performance.<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">
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There are plans to make shard useful for more generic use cases in the near term. When we get there, we will support quota too on sharded files.<br>
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That's a *good* news. BTW we also have a plan to implement this part. Any suggestions?<br></blockquote><div><br></div><div>That's nice. We could have a chat on #gluster-dev in Freenode if you want.<br><br></div><div>-Krutika<br><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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-Krutika<br>
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-- <br>
Thanks<br>
-Xie<br>
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