[sheepdog] [PATCH] sheep: cache sha1 digest for read-only objects

[Liu Yuan]

On 05/14/2013 03:10 PM, MORITA Kazutaka wrote:
> +
> +	if (!is_xattr_enabled(obj_path)) {
> +		sd_eprintf("xattrs are not enabled on %s", obj_path);
> +		return SD_RES_EIO;
> +	}
> +

This is not needed, MD checks it already.

> The contents of read-only objects are immutable.  We can cache their
> sha1 digests as extended attributes for the next sha1 calculation.
> With this patch, I can complete 'collie vdi check' of a 4 GB snapshot
> volume in 0.2 seconds.

Any number for recovery boost?

Thanks,
Yuan