Am 14.05.2012 13:22, schrieb Sami Siren:
Sharding is (nearly) always slower than using one big index with sufficient
hardware resources. Only use sharding when your index is too huge to fit
into one single machine.
If you're not constrained by CPU or IO, in other words have plenty of
CPU cores available together with for example separate hard discs for
each shard splitting your index into smaller shards can in some cases
make a huge difference in one box too.
Do you have an example?
This is hard to believe. If you've several shard on the same machine,
you'll need that much memory that each shard has enough for all its
caches and duch. With that lot of memory, a single Solr core should be
really fast.
If dividing the index is the reason, then a software RAID 0 (striping)
should be much better.
The only point I see is the concurrent search for one request. Maybe,
for large requests, this might outweigh the sharding overhead, but only
for long-running requests without disk I/O. I only see the case when
using very complicated query functions. And, this only stays true as
long as you don't run multiple concurrent requests.
Greetings,
Kuli
