On the btrfs list it was mentioned that a patch may be queued up for the 3.5 kernel to address unnecessary retries by the block layer for media errors by this patch: http://patchwork.ozlabs.org/patch/156540/ # ATA and SATA drives have had built-in retries for media errors # for as long as they've been commonplace in computers (early 1990s). # # When libata stumbles across a bad sector, it can waste minutes # sitting there doing retry after retry before finally giving up # and letting the higher layers deal with it. # # This patch removes retries for media errors only. -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC This email may come with a PGP signature as a file. Do not panic. For more info see: http://en.wikipedia.org/wiki/OpenPGP