On Thu, Dec 5, 2013 at 5:07 PM, Yann Ylavic <[email protected]> wrote:
> On Thu, Dec 5, 2013 at 4:05 PM, Jim Jagielski <[email protected]> wrote: > >> There hardly seemed any consensus on the patch... It also >> seems that it adds more cycles to Apache on the front to >> reduce a race condition that can't really be removed. >> > > I don't think more cycles are added by this patch. > What is done is that ap_proxy_http_request() is split in two functions, > the prefetch part is now in ap_proxy_http_prefetch(), and > ap_proxy_http_prefetch()+ap_proxy_http_request() has no more cycles than > the previous ap_proxy_http_request(). > Unless you consider dereferencing pointer arguments a cycles-overhead > compared to using local variables... > That's not totally true, maybe you refer to this cycles : + /* Preserve the header/input brigades since they may be retried. */ + input_bb = apr_brigade_create(p, backconn->bucket_alloc); + header_bb = apr_brigade_create(p, backconn->bucket_alloc); + proxy_buckets_lifetime_transform(r, input_brigade, input_bb); + proxy_buckets_lifetime_transform(r, header_brigade, header_bb); mod_proxy may need to setaside these buckets.
