[Xapian-discuss] Xapian on SSD vs SATA

[Arjen van der Meijden]

On 23-10-2009 14:11, Henry wrote:
> As you can see, keyword queries are quicker, but lack the wow! factor.
> Phrase queries *really* benefit - 10x faster is what one would expect 
> from using an SSD.

Why would you have that expectation? If most of the data you're looking 
at fits in RAM, then SSD vs normal disk will see only small differences 
(not that 2 vs 1.2 is insignificant).

> So,... to conclude:  SSDs provide excellent gains for phrase queries - 
> something 99.9999% of users won't use anyway :(

Well, the fastest queries didn't probably need much optimization 
anyway... So perhaps you shouldn't bother too much about those faster 
queries, they're fast enough to begin with.
Apart from that; You should probably attempt to test a mix of queries to 
see how much influence a running phrase query has on the other queries 
at that time.

But your results are similar to ours, which I posted a while back to the 
list. The fast queries are cpu-bound (on the top-nehalem), even forcing 
the system to have only a few GB of memory didn't make it IO-bound in a 
our tests.

Best regards,

Arjen