Yes, this works for me.
Thanks for looking into this.
-radha
On Thu, Feb 19, 2009 at 10:26 AM, Jens Axboe <jens.axboe@xxxxxxxxxx> wrote:
> On Thu, Feb 19 2009, Radha Ramachandran wrote:
>> Yes, that makes sense for a randwrite operation.
>> But is it acceptable to allow norandommap with verify for
>> read/randomread only operations with no writes involved. The case Iam
>> specifically interested in is doing sequential writes followed by
>> sequential reads (with verify) and then randomaccess reads (with
>> verify). For a small enough block size on a large enough drive the
>> norandommap takes up too much memory.
>
> The memory usage is indeed problematic, that is why the option exists.
> I'd be very happy to slim that down...
>
> What you suggest will work, but only for fixed size blocks. Once you
> have varying block sizes, a given random minimum block offset may be
> inside a verify block, not at the start of it.
>
> So I guess the 'norandommap disables verify' can be relaxed to
> 'norandommap disables verify IFF non-fixed block sizes are used'. I'm
> assuming that would work for you? Please try the below patch. If
> succesful, I'll augment it with an updated HOWTO description.
>
> diff --git a/init.c b/init.c
> index 95c282a..001e5c4 100644
> --- a/init.c
> +++ b/init.c
> @@ -206,6 +206,13 @@ static int setup_rate(struct thread_data *td)
> return 0;
> }
>
> +static int fixed_block_size(struct thread_options *o)
> +{
> + return o->min_bs[DDIR_READ] == o->max_bs[DDIR_READ] &&
> + o->min_bs[DDIR_WRITE] == o->max_bs[DDIR_WRITE] &&
> + o->min_bs[DDIR_READ] == o->min_bs[DDIR_WRITE];
> +}
> +
> /*
> * Lazy way of fixing up options that depend on each other. We could also
> * define option callback handlers, but this is easier.
> @@ -269,8 +276,10 @@ static int fixup_options(struct thread_data *td)
> if (!o->file_size_high)
> o->file_size_high = o->file_size_low;
>
> - if (o->norandommap && o->verify != VERIFY_NONE) {
> - log_err("fio: norandommap given, verify disabled\n");
> + if (o->norandommap && o->verify != VERIFY_NONE
> + && !fixed_block_size(o)) {
> + log_err("fio: norandommap given for variable block sizes, "
> + "verify disabled\n");
> o->verify = VERIFY_NONE;
> }
> if (o->bs_unaligned && (o->odirect || td->io_ops->flags & FIO_RAWIO))
>
> --
> Jens Axboe
>
>
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