Re: spamprobe-1.1x7 released

Jacob S wrote:
> On Wed, 30 Mar 2005 10:12:53 -0500
> Brian Burton <[email protected]> wrote:
>>The record size in a hash database should be the same on 64 bit 
>>processors as it is on 32 bit processors.  I haven't tested that
>>though  since I don't have a 64 bit system to test on.
>>
>>A great test to run would be to build a hash database on a 32 bit 
>>system, export that to a file, import that file into a database on a
>>64  bit system, export on that 64 bit system to a new file and then
>>diff the  two export files.  They should be identical.
> 
> hmm... I was thinking previously (with PBL) the size difference was only
> noticed when doing a du/ls -l on the db. When exported to a text file,
> both dbs were the same size. Is there something different about hashing
> that I don't know about, or is this a case where I don't know anything
> and should keep quiet? :-) 

You are correct that on PBL and BDB the record size would be different 
on a 64 bit CPU because I wrote records using the native word size. 
Basically I took a struct and wrote all of its bits directly so if a 
long was 8 bytes instead of 4 the record size would double.

The hash is different since its whole reason for existence is to 
minimize disk space consumption.  With the hash format I have code that 
explicitly writes a fixed number of bytes for each record.

The hash file code assumes that records have a fixed size independent of 
word size on the machine SP is running on.  I think I got that code 
right but I can't test it here.  The test I outlined was to verify that 
I don't have a bug which might corrupt the hash file on 64 bit CPUs.

Thanks,
++Brian


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