Re: [Ext2-devel] [PATCH] JBD: log space management optimization

[Stephen C. Tweedie]

Hi,

On Mon, 2005-01-24 at 20:22, Alex Tomas wrote:

> during truncate ext3 calls journal_forget() for freed blocks, but
> before these blocks go to the transaction and jbd reserves space
> in log for them (->t_outstanding_credits). also, journal_forget()
> removes these blocks from the transaction, but doesn't correct
> log space reservation. for example, removal of 500MB file reserves
> 136 blocks, but only 10 blocks go to the log. a commit is expensive
> and correct reservation allows us to avoid needless commits. here
> is the patch. tested on UP.

> +drop:
> +	if (drop_reserve) {
> +		/* no need to reserve log space for this block -bzzz */
> +		handle->h_buffer_credits++;
> +	}
> +

Looks good to me.

--Stephen

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/