[Gluster-users] About read-subvolume

[Vikas Gorur]

On Apr 7, 2010, at 4:55 PM, Chris Jin wrote:

> Hi, I got a question about read-subvolume.
> 
> Actually I want to do an replicate translator across two servers, but
> only read from the local server using read-subvolume option. I turned
> off self-healing because I want to do self-healing manually. When I
> limited the bandwidth between the client and the other server, the
> reading was really slow, but what I expected is the client only contacts
> the local server.
> 
> After searching on the internet, I found that we must suffer the latency
> of checking the metadata on both servers, even when we only need to read
> from one server.
> 
> So my question is if there is a way to stop checking the metadata on
> both servers when reading only one server.

With read-subvolume set, readv() is sent only to the specified subvolume.
However, lookup(), open(), and close() have to go to both subvolumes. There is no way
to disable this.

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Vikas Gorur
Engineer - Gluster, Inc.
+1 (408) 770 1894
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