>>>>> "Mathijs" == Mathijs Brands <mathijs@stripped> writes:
<cut>
Mathijs> What about tables bigger than 2 GB? Does MySQL use the increased
> addressingspace
Mathijs> on a 64 bit architecture?
>>
>> Yes; MySQL can handle big files if the underlaying OS supports it.
>>
>> The new RAID option can expand the barrier on 32 bit systems, but this
>> is still in testing!
Mathijs> I was talking about mmap. Solaris i86 will only let me mmap a maximum of 2 GB
> (one big
Mathijs> chunk) and the same goes for FreeBSD. So if a single table contains more than
> 2 GB of
Mathijs> data, it cannot be mmap-ed in one piece. This is what I meant.
Currently the code in MySQL that uses memmap assumes it can mmap
everything in one hunk. If this doesn't work it will fallback to
normal read/write.
Anyway, I think it's on Solaris you can see the biggest improvements
when using mmap as all read/writes are done with memmap (or so I have
been told).
I actually don't know how mmap works on 64 bit architectures; If one
can allocate bigger hunks than 2G there, there is no reason why it
wouldn't work with MySQL.
Mathijs> If I assume you thought I was referring to the size of files, then the RAID
> remark
Mathijs> suddenly starts to make sense :)
Sorry for the confusion; Yes, that was what I thought
Regards,
Monty
