On Thu, Sep 18, 2008 at 01:26:09PM +0200, Nils Goroll wrote: > Thank you very much for correcting my long-time misconception. > > On the other hand, isn't there room for improvement here? If it was > possible to break large writes into smaller blocks with individual > checkums(for instance those which are larger than a > preferred_read_size parameter), we could still write all of these with > a single RAIDZ(2) line, avoid the RAIDx write penalty and improve read > performance because we'd only need to issue a single read I/O for each > requested block - needing to access the full RAIDZ line only for the > degraded RAID case.
Don't forget that the parent block contains the checksum so that it can be compared. There isn't room in the parent for an arbitrary number of checksums as would be required with an arbitrary number of columns. -- Darren _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
