Re: [BK PATCH 1/2] Remove NGROUPS hardlimit (resend w/o qsort)

From: Andrew Morton (
Date: Thu Nov 14 2002 - 21:41:47 EST

Tim Hockin wrote:
> > 10,000 bits isn't much. Maybe:
> That's 10000 USED bits. Remember groups are non-contiguously allocated. If
> a task is a member of just groups 32767 and 65535, you'll get one bit per
> page used, and when they call getgroups() you need to pull it apart and
> return an array of gid_t.

Well that's what I was asking.

What is the maximum group ID? 0xffffffff?

In that case a radix tree _might_ suit. All you need to put in the
node is a (void *)1 or (void *)0. But it won't be very space-efficient
for really sparse groups.
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This archive was generated by hypermail 2b29 : Fri Nov 15 2002 - 22:00:35 EST