Safe to read index while it is being written to?

Ruby Apps Ferret
1

Is it safe to open the index to do searches on while another process is
writing to the index?

2

Dan Yelp wrote:

Is it safe to open the index to do searches on while another process is
writing to the index?

I don’t know the technical details, but I have experienced some problems
when trying to do this. I have an index of about 275K short documents,
and in an ideal world I’d be updating it continuously. Right now I wait
until the off-hours because if I’m updating the index at all, searches
tend to cause my mongrel procs to either hang (100% CPU util), or
segfault (documented in a ticket on the ferret track). I have processes
in place to correct these problems when they occur, but it’s still
discouraging because I can’t keep the data as fresh as I’d like it to
be.

Jim

3

On Nov 2, 2006, at 6:47 PM, Dan Yelp wrote:

Is it safe to open the index to do searches on while another
process is
writing to the index?

Yes. The caveat is that an IndexReader or IndexSearcher only sees
what was indexed at the time the index was opened, and will not see
documents written since. Seeing changes requires re-opening. See
Solr discussions on auto-warming if you need faster searches out of
the gate.

Erik
4

oops… i replied as if this was the java-user list, not the Ferret
one. sorry for mixing up my languages. ai ya!