Commit d217d1a1 authored by Graham Leggett's avatar Graham Leggett
Browse files

mod_buffer: Optimise the buffering of heap buckets when the heap 

buckets stay exactly APR_BUCKET_BUFF_SIZE long.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@718125 13f79535-47bb-0310-9956-ffa450edef68
parent 27bff06d

CHANGES

+4 −0
Original line number Diff line number Diff line
@@ -2,6 +2,10 @@ 
Changes with Apache 2.3.0

[ When backported to 2.2.x, remove entry from this file ]



  *) mod_buffer: Optimise the buffering of heap buckets when the heap

     buckets stay exactly APR_BUCKET_BUFF_SIZE long. [Graham Leggett,

     Ruediger Pluem]



  *) mod_buffer: Optional support for buffering of the input and output

     filter stacks. Can collapse many small buckets into fewer larger

     buckets, and prevents excessively small chunks being sent over

modules/filters/mod_buffer.c

+24 −2
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ static apr_status_t buffer_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { 
    request_rec *r = f->r;

    buffer_ctx *ctx = f->ctx;

    apr_status_t rv = APR_SUCCESS;

    int move = 0;



    /* first time in? create a context */

    if (!ctx) {
@@ -81,6 +82,11 @@ static apr_status_t buffer_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { 
        return ap_pass_brigade(f->next, bb);

    }



    /* Empty buffer means we can potentially optimise below */

    if (APR_BRIGADE_EMPTY(ctx->bb)) {

        move = 1;

    }



    while (APR_SUCCESS == rv && !APR_BRIGADE_EMPTY(bb)) {

        const char *data;

        apr_off_t len;
@@ -146,10 +152,26 @@ static apr_status_t buffer_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { 
         */

        if (APR_SUCCESS == (rv = apr_bucket_read(e, &data, &size,

                APR_BLOCK_READ))) {



            /* further optimisation: if the buckets are already heap

             * buckets, and the buckets stay exactly APR_BUCKET_BUFF_SIZE

             * long (as they would be if we were reading bits of a

             * large bucket), then move the buckets instead of copying

             * them.

             */

            if (move && APR_BUCKET_IS_HEAP(e)) {

                APR_BUCKET_REMOVE(e);

                APR_BRIGADE_INSERT_TAIL(ctx->bb, e);

                if (APR_BUCKET_BUFF_SIZE != size) {

                    move = 0;

                }

            } else {

                apr_brigade_write(ctx->bb, NULL, NULL, data, size);

                apr_bucket_delete(e);

            }



        }



        apr_bucket_delete(e);

    }



    return rv;