[Libguestfs] [PATCH] generator: small optimization of pod2text cache memoization
Richard W.M. Jones
rjones at redhat.com
Thu Mar 12 19:12:16 UTC 2015
On Thu, Mar 12, 2015 at 06:09:40PM +0100, Pino Toscano wrote:
> Instead of save every time there's a new element in the cache, batch the
> saving to disk every 100 changes, saving the unsaved remainder at the
> exit.
>
> While not a big optimization, this reduces a bit the disk usage during
> generator run.
> ---
> generator/utils.ml | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/generator/utils.ml b/generator/utils.ml
> index 3a62084..1b00ce5 100644
> --- a/generator/utils.ml
> +++ b/generator/utils.ml
> @@ -291,10 +291,22 @@ let pod2text_memo : (memo_key, memo_value) Hashtbl.t =
> v
> with
> _ -> Hashtbl.create 13
> -let pod2text_memo_updated () =
> +let pod2text_memo_unsaved_count = ref 0
> +let pod2text_memo_atexit = ref false
> +let pod2text_memo_save () =
> let chan = open_out pod2text_memo_filename in
> output_value chan pod2text_memo;
> close_out chan
> +let pod2text_memo_updated () =
> + if not (!pod2text_memo_atexit) then (
> + at_exit pod2text_memo_save;
> + pod2text_memo_atexit := true;
> + );
> + pod2text_memo_unsaved_count := !pod2text_memo_unsaved_count + 1;
> + if !pod2text_memo_unsaved_count >= 100 then (
> + pod2text_memo_save ();
> + pod2text_memo_unsaved_count := 0;
> + )
>
> (* Useful if you need the longdesc POD text as plain text. Returns a
> * list of lines.
> --
> 2.1.0
Looks sensible, ACK.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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