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SetLimits
Prototype: function SetLimits ( $offset, $limit, $max_matches=1000, $cutoff=0 )
Sets offset into server-side result set ($offset) and amount of matches
to return to client starting from that offset ($limit). Can additionally
control maximum server-side result set size for current query ($max_matches)
and the threshold amount of matches to stop searching at ($cutoff).
All parameters must be non-negative integers.
First two parameters to SetLimits() are identical in behavior to MySQL
LIMIT clause. They instruct searchd to return at
most $limit matches starting from match number $offset.
The default offset and limit settings are 0 and 20, that is, to return
first 20 matches.
max_matches setting controls how much matches searchd
will keep in RAM while searching. All matching documents will be normally
processed, ranked, filtered, and sorted even if max_matches is set to 1.
But only best N documents are stored in memory at any given moment for performance
and RAM usage reasons, and this setting controls that N. Note that there are
two places where max_matches limit is enforced. Per-query
limit is controlled by this API call, but there also is per-server limit
controlled by max_matches setting in the config file. To prevent
RAM usage abuse, server will not allow to set per-query limit
higher than the per-server limit.
You can't retrieve more than max_matches matches to the client application.
The default limit is set to 1000. Normally, you must not have to go over
this limit. One thousand records is enough to present to the end user.
And if you're thinking about pulling the results to application
for further sorting or filtering, that would be much more efficient
if performed on Sphinx side.
$cutoff setting is intended for advanced performance control.
It tells searchd to forcibly stop search query
once $cutoff matches had been found and processed.
