Matthew J. Dovey wrote:
>>It may indicate a decently fast database, but for a local
>>network, latencies should be in the order of 0.2ms
>
>
> True, but the motivation behind SRW/SRU isn't really for local
> applications on the local subnet (that isn't to say there isn't a role
> there) as opposed to services over the internet.
>
>
>>In 36 ms I can ping servers in
>>nearby countries.
>
>
> Currently my pings to the Library of Congress from the UK is 78ms.
> However, we aren't talking about single (32 bytes?) ICMP packets for
> SRW/SRU, but rather a chunk of XML over http which would typically take
> several TCP packets to send (so we would be looking at some multiple of
> 36ms/78ms plus overhead caused by different packets taking different
> routes and packet re-assembly). So I would be surpised if typical
> network latency of an SRU request to the Library of Congress from the UK
> was less than a few hundred ms.
 From DK, I ping LOC in approx 105 ms . If I choose an infrequent term,
SRU search takes 250-500 ms (includes SRU handling + search at the
target). Had it been based on Axis it would have been 700-950 ms.

/ Adam

> Matthew
>