分区会提高MySQL INSERT的速度吗？

I'm doing a lot of INSERTs via LOAD DATA INFILE on MySQL 5.0. After many inserts, say a few hundred millions rows (InnoDB, PK + a non-unique index, 64 bit Linux 4GB RAM, RAID 1), the inserts slow down considerably and appear IO bound. Are partitions in MySQL 5.1 likely to improve performance if the data flows into separate partition tables? I'm doing a lot of INSERTs via LOAD DATA INFILE