Why is MySQL nearly twice as fast on Linux/AMD64 Vs. FreeBSD/AMD64?

[JG]

More benchmarks...

My hardware is more than adequate for the my-huge.cnf configuration,
so this time I used the my-huge.cnf for my /etc/my.cnf

... and my results were the worst I've seen so far. Go figure.


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FreeBSD 5.2-CURRENT FreeBSD 5.2-CURRENT #0: Tue May 18 07:17:39 PDT 2004
(-CURRENT above has the ULE + KSE patch applied)

Kernel compiled with SCHED_ULE & debugging disabled.

MySQL Ver 4.0.20 for portbld-freebsd5.2 on amd64 (FreeBSD port: 
mysql-server-4.0.20)
   with mysql40-server.diffs patch applied

Port options:

BUILD_OPTIMIZED=yes
BUILD_STATIC=yes

Compiled with libpthreads

Using my-huge.cnf


BENCHMARK RESULTS:

Generating 500000 records...
Creation of 500000 records took 202 seconds.
Average of 2475.2475247525 records per second.
Creating records for 10 seconds...
Created 21396 records in 10 seconds.
Average of 2139.6 records per second.
Creating random 50000 md5 hash records.
Creation of 50000 random md5 hash inserts took 22 seconds.
Average of 2272.7272727273 records per second.
Creating random md5 hash records for 10 seconds...
Created 21591 random records in 10 seconds.
Average of 2159.1 records per second.

Your databases overall average score is 2261.6686993699 records per second.



VS.

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LINUX MANDRAKE 10.0 RC1 w/"OUT OF THE BOX" MySQL installation
MySQLd Ver 4.0.18 for mandrake-linux-gnu on x86_64 (Source distribution)
Linux amd64m 2.6.3-9mdksmp #1 SMP Mon Apr 19 10:48:13 CEST 2004 x86_64 
unknown unknown GNU/Linux

Benchmark result summary:

Generating 500000 records...
Creation of 500000 records took 89 seconds.
Average of 5617.9775280899 records per second.
Creating records for 10 seconds...
Created 50547 records in 10 seconds.
Average of 5054.7 records per second.
Creating random 50000 md5 hash records.
Creation of 50000 random md5 hash inserts took 9 seconds.
Average of 5555.5555555556 records per second.
Creating random md5 hash records for 10 seconds...
Created 50864 random records in 10 seconds.
Average of 5086.4 records per second.

Your databases overall average score is 5328.6582709114 records per second
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