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

[JG]

Also tried with the MySQL 5.0.0a port, same results basically:



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FreeBSD 5.2-CURRENT FreeBSD 5.2-CURRENT #0: Tue May 18 07:17:39 PDT 2004

With SCHED_ULE & debugging turned off in kernel.

amd64f# ldd /usr/local/libexec/mysqld
/usr/local/libexec/mysqld:
         libpthread.so.1 => /usr/lib/libpthread.so.1 (0x2009ab000)
         libz.so.2 => /lib/libz.so.2 (0x200ad5000)
         libcrypt.so.2 => /lib/libcrypt.so.2 (0x200be4000)
         libstdc++.so.4 => /usr/lib/libstdc++.so.4 (0x200cfe000)
         libm.so.2 => /lib/libm.so.2 (0x200ee5000)
         libc.so.5 => /lib/libc.so.5 (0x201005000)

amd64f# /usr/local/libexec/mysqld --version
Ver 5.0.0-alpha for portbld-freebsd5.2 on amd64 (FreeBSD port: 
mysql-server-5.0.0_2)

 From the ports Makefile:
CONFIGURE_ARGS= --localstatedir=${DB_DIR} \
                 --without-debug \
                 --without-readline \
                 --without-libedit \
                 --without-bench \
                 --without-extra-tools \
                 --without-libwrap \
                 --with-mysqlfs \
                 --with-vio \
                 --with-low-memory \
                 --with-comment='FreeBSD port: ${PKGNAME}' \
                 --enable-thread-safe-client

Benchmark Results:

Generating 500000 records...
Creation of 500000 records took 167 seconds.
Average of 2994.0119760479 records per second.
Creating records for 10 seconds...
Created 32912 records in 10 seconds.
Average of 3291.2 records per second.
Creating random 50000 md5 hash records.
Creation of 50000 random md5 hash inserts took 16 seconds.
Average of 3125 records per second.
Creating random md5 hash records for 10 seconds...
Created 29294 random records in 10 seconds.
Average of 2929.4 records per second.

Your databases overall average score is 3084.902994012 records per second.
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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:

Your databases overall average score is 5328.6582709114 records per second

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