[OPEN-ILS-DEV] PATCH revised: osrf_hash.[ch] (performance tweak)

[Scott McKellar]

--- Scott McKellar <mck9 at swbell.net> wrote:

> This patch boosts the performance of an osrfHashIterator a bit, by
> reusing the "current" buffer whenever possible instead of freeing and
> reallocating it on every iteration.

The patch attached here supercedes and replaces the patch I posted
a couple of days ago.

The change: in osrfHashIteratorReset, I had placed a nul in the
first character of itr->current.  However it is possible to call
this function when itr->current is still NULL.  Oops.

In the revised patch, I apply the nul only if itr->current is 
not NULL.

----------------------

I have experimented with a partial implementation of the ideas I
wrote about earlier today, using a doubly linked list instead of
an osrfStringArray to represent the sequence in which the entries
were added.

I modified my benchmark program to compare two different ways to
traverse an osrfHash: the old way (by indexing through the
osrfStringArray and doing hashed lookups) and the new way (using
a linked list).

The new kind of traversal is consistently about 40 times as fast.

Scott McKellar
http://home.swbell.net/mck9/ct/

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