How fast is perl hash select? -

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i use perl hash store ip -> hostname pairs. have millions of it.

i cache gethostbyip syscall in hash %hostname{$ip}.

memory not issue. time is.

how fast perl hash search works in condition?

will work faster if use mysqldb or berkleydb instead?

assuming have sufficient ram hold of data, in-memory lookups always faster retrieving data external source (disk, database, etc.) because ram fast , i/o operations slow.

if can't hold in ram, becomes less predictable , may need benchmark determine what's faster particular combination of program , hardware.


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