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Practical size limit of Dictionaries with a 64 bit vm

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Wouter Gazendam

Practical size limit of Dictionaries with a 64 bit vm

Hi,

With the current 32 bit vm's dictionary acccess starts to become slow
with 20000+ items, due to the reduced precision of #identityHash'es.
Does anyone know what the practical size limit would be with a 64 bit vm?
How many bits precision (is that how one should call this?) will the
#identityHash be with a 64 bit vm?

Tnx,

Wouter Gazendam
CosmoCows B.V.

Eliot Miranda-2

Re: Practical size limit of Dictionaries with a 64 bit vm

Hi Wouter,

On 5/1/07, Wouter Gazendam <[hidden email]> wrote:

Hi,

With the current 32 bit vm's dictionary acccess starts to become slow
with 20000+ items, due to the reduced precision of #identityHash'es.
Does anyone know what the practical size limit would be with a 64 bit vm?
How many bits precision (is that how one should call this?) will the
#identityHash be with a 64 bit vm?

See ObjectMemory class>>maximumIdentityHashValue. The 32-bit VM has a 14-bit identity hash and the 64-bit VM has a 20-bit identityHash.