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**To**:**tech-kern%NetBSD.org@localhost****Subject**:**Re: radix tree implementation for quota ?****From**:**David Holland <dholland-tech%netbsd.org@localhost>**- Date: Tue, 30 Nov 2010 12:57:13 +0000

On Mon, Nov 29, 2010 at 11:12:21AM -0500, der Mouse wrote: > Without any real data on what UID distribution looks like in practice, > we're all speculating in a vacuum here. Just for shits and giggles I ran this on a real password file with about 350 users that's had lots of churn since it was first established. Using Joerg's hash with a table of size 512 gave 90 collisions; using x % 509 (the nearest available prime) gave 91. For comparison I tried some of the (more expensive) hashes from db4 and got 111, 94, and 84. None of the hash functions generated significant hotspots. It seems like a nonissue. (Of course, hashing 350 things isn't exactly a big challenge...) -- David A. Holland dholland%netbsd.org@localhost

**Follow-Ups**:**Re: radix tree implementation for quota ?***From:*Sad Clouds

**References**:**Re: radix tree implementation for quota ?***From:*Sad Clouds

**Re: radix tree implementation for quota ?***From:*Manuel Bouyer

**Re: radix tree implementation for quota ?***From:*David Laight

**Re: radix tree implementation for quota ?***From:*Sad Clouds

**Re: radix tree implementation for quota ?***From:*Joerg Sonnenberger

**Re: radix tree implementation for quota ?***From:*Sad Clouds

**Re: radix tree implementation for quota ?***From:*Joerg Sonnenberger

**Re: radix tree implementation for quota ?***From:*Sad Clouds

**Re: radix tree implementation for quota ?***From:*Joerg Sonnenberger

**Re: radix tree implementation for quota ?***From:*der Mouse

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