Robert Welsh wrote:
> You should change maxmem
>
> FYI : 2^20 = 1megabyte.
>
> you are most likely thrashing yourself to death.
>
> if you have a 2 gig of ram i would suggest making
>
> maxmem = 2^28 or 2^29
When I first read this I thought it would make an enormous amount of
difference, since 1 Mybte is tiny. However, note that the estimation
is still done plane-by-plane -- see e.g. lines 504-5 and 617-8 of spm_spm.
For data with 109*109 plane-size (e.g. the standard SPM5 template) a
complete plane is only about 100 kbyte of memory, so with e.g. 1000
scans, there are only about 91 blocks per plane with the default
maxmem size, and any maxmem above 2^27 (128 Mbyte) will be no better
than 2^27. Of course, setting it to 2^29 should do no harm if have
more memory than that, and if you do have *loads* of images then it
will help.
So while this will make a difference, I'm not sure it will entirely
explain Bas's concerns -- though, Bas, back to you to say if it has...
Best,
Ged.
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