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in reply to Re: Perl solution for storage of large number of small files
in thread Perl solution for storage of large number of small files

InnoDB must flush the log to disk at each transaction commit if that transaction made modifications to the database. ... constrains the number of commits to the same 167th of a second

unless you set innodb_flush_log_at_trx_commit to 0, which switches it to flush once a second.
http://dev.mysql.com/doc/refman/5.0/en/innodb-parameters.html

HTH, andye