KDC performance test - lookaside cache impact, testing framework

Tom Yu tlyu at MIT.EDU
Thu Apr 5 18:13:20 EDT 2012

Greg Hudson <ghudson at MIT.EDU> writes:

> However, the current lookaside cache is a linked list.  If the KDC is
> loaded enough to take almost a full second to answer a request, there
> are likely to be hundreds or thousands of entries in the cache.
> Searching a linked list of that size will probably take longer than
> processing a request--and, of course, that cost is paid for every
> request, not just the retransmits.
> It would be a fairly simple matter to make a hash table for the
> lookaside cache, which should reduce its cost to much less than the cost
> of processing a request, making it potentially worthwhile.

A while ago, someone (Mark Eichin, maybe?) implemented an array-based
lookaside cache, which allegedly produced measurable speed
improvements compared to the linked list cache.

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