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Hello,
On Fri, 28 Jun 2002, Daniel Burke wrote:
> In anticipation of our capacity requirements growing,
> we had decided it was necessary to increase the
> connection table size. The value it was at was 16,
> based on our calculations we needed to bump it to 26
> to handle what were will be throwing at it.
It is insane to use 26. That means 2^26 * space for
2 pointers. On x86 it takes 512MB just for allocating
empty hash table with 2^26 d-linked lists. Refer to the
HOWTO for calculating the best hash table size according
to the number of connections. You can select the size (POWER)
in this way:
2^POWER = AVERAGE_NUM_CONNS/10
The magic value 10 in this case is the average number of
conns expected in one d-linked list, the lookup is slower
for more conns.
Example:
POWER=16 => 65536 rows => 655360 conns, ~10 on each row
Regards
--
Julian Anastasov <ja@xxxxxx>
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