Thanks Olaf.

>
> <al...@ipac.caltech.edu> schrieb im Newsbeitrag
> news:634ea812687a6d75a1ddf17adce883fc.squir...@webmail.ipac.caltech.edu...
>
>
>> >> My primary concern now is to prevent a dead-lock.
>> > That seems to make sense now (I assume you're working
>> > "near a deadlock" with your multipe-client-requests, not
>> > going to sleep properly before the next retry).
>>
>> Still makes no sense to me, how the absence of re-try code,
>> while very silly - yes;), can explain the vast difference in
>> performance I see between the "local-disk" scenario and
>> the over-NFS scenario?
>
> Such things can be tested - just start the same Job you performed
> earlier locally, now against NFS (with only one single writer-instance).
> And that shouldn't be all that much slower than against the local disk.
> If it already is (whilst using the DB over NFS exclusively), well - then
> something is probably wrong with your NFS (only Samba-Shares
> here - but in case of single Writer against the share, it does Ok -
> not as fast as against the local disk - but "fast enough" (just what
> one expects due to the involved sockets under the hood).
> Then, if you find nothing wrong with the single-writer-performance,
> increase the writers-count step-by-step, to take a look at the
> additional locking-overhead.
>
> Same thing in the other way round (which would be my first test)...
> do your concurrency-tests against the local disk - I mean, you
> already have many CPU-cores apparently on your Client-machine -
> let this machine act somewhat like an AppServer then (without
> a "socket-interface"), local processes/threads working concurrently
> against the local disk. And there you have the "pure effects" -
> easy to see then, if there's something wrong with your busy-
> handling - or not - and maybe check your threading-settings
> which you use in the sqlite-binary (we use '2' here, and no shared
> cache, each thread having its own connection-handle).
>
> Olaf
>
>
>
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