32GB/device swap limit on amd64

Peter Wemm peter at wemm.org
Mon May 2 00:42:30 PDT 2005

On Sunday 01 May 2005 03:06 pm, Kris Kennaway wrote:
> Looks like amd64 has the following limit, which is the same as on
> i386:
> WARNING: reducing size to maximum of 67108864 blocks per swap unit
> Can this be easily fixed on amd64?
> Kris

This looks like its a subr_blist.c problem:

         * If we go beyond this, we get overflows in the radix
         * tree bitmap code.
        mblocks = 0x40000000 / BLIST_META_RADIX;
        if (nblks > mblocks) {
                printf("WARNING: reducing size to maximum of %lu blocks per swap unit\n",
                nblks = mblocks;

sys/blist.h:#define BLIST_META_RADIX 16
Peter Wemm - peter at wemm.org; peter at FreeBSD.org; peter at yahoo-inc.com
"All of this is for nothing if we don't go to the stars" - JMS/B5

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