As co-contributor of the latest piece of code about SSS/VLV, I will try and
give some explanations : VLV does not give a clean way to destroy the server
side sorted entries list.
The SSS/VLV overlay implementation is using a limit in order to manage
memory limits : a connection will be limited to a specified number of paged
searches. The only way to reset this limit is to close and reopen a
Maybe a timeout will be a good idea also but this is not implemented now.
2011/7/1 Chris Card <ctcard(a)hotmail.com>
> >>> When using the sssvlv overlay how does the client tell the server
> >> sort request can be thrown away, so that sort requests don't hang
> >> sssvlv-max or sssvlv-maxpercon are exceeded?
> >> There is no official mechanism for this. This is a flaw in the
> >> specification. For Paged Results you simply send a followup request
> >> pagesize set to zero, but that doesn't apply for VLV.
> >> I believe in our current implementation, if you send a new Paged
> >> request on a connection that has VLVs outstanding, one of the VLVs
> >> aborted. Unfortunately, if you have multiple VLVs outstanding, there's
> >> to determine which one gets aborted. (Apparently this was overlooked
> >> patching the overlay to allow multiple VLVs on a connection...)
> > Thanks for the info.
> > Is it the case that sort requests are associated with a particular
> What does RFC2891 say?
As far as I can see it doesn't mention connections.
However, looking at the code in sssvlv.c, it appears that a sort operation
is associated with a session, and a session
is associated with a connection, e.g. on line 900 of sssvlv.c in
sort_conns[op->o_conn->c_conn_idx][sess_id] = so;
> >> From my testing it seems that a sort request will remain active in the
server evenif the client disconnects, which doesn't seem right.
> How are you determining that this is the case?
I'm using ldapsearch to test requests with sss and vlv controls. After
running several such ldapsearch commands I get an
error from the server :
# search result
result: 51 Server is busy
text: Other sort requests already in progress
I am assuming that the connection to the server is dropped when the
ldapsearch command terminates; that
must certainly be the case at the client end since the process no longer
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