I've been running a node with this patch on a production machine for 5 days and am seeing marked improvements. The instance hasn't needed to be restarted due to "ngx_slab_alloc() failed: no memory". The shared memory usage has been growing at a far slower rate compared to a node without the patch. Also, not seeing any significant increase in CPU usage.
nginx/1.2.9 Mixture of HTTP/HTTPS traffic 400,000 to 700,000 concurrent connections Linux 3.2.0-40-generic x86_64 It's a dedicated instance for Wandenberg's https://github.com/wandenberg/nginx-push-stream-module On Tue, Aug 6, 2013 at 1:19 PM, Wandenberg Peixoto <wandenb...@gmail.com> wrote: > > Hello! > > Thanks for your help. I hope that the patch be OK now. > I don't know if the function and variable names are on nginx pattern. > Feel free to change the patch. > If you have any other point before accept it, will be a pleasure to fix it. > > > --- src/core/ngx_slab.c 2013-05-06 07:27:10.000000000 -0300 > +++ src/core/ngx_slab.c 2013-07-31 00:21:08.043034442 -0300 > @@ -615,6 +615,26 @@ fail: > > > static ngx_slab_page_t * > +ngx_slab_merge_with_neighbour(ngx_slab_pool_t *pool, ngx_slab_page_t *page) > +{ > > + ngx_slab_page_t *neighbour = &page[page->slab]; > + if (((ngx_slab_page_t *) neighbour->prev != NULL) && (neighbour->next != > NULL) && ((neighbour->prev & NGX_SLAB_PAGE_MASK) == NGX_SLAB_PAGE)) { > + page->slab += neighbour->slab; > > + > + ((ngx_slab_page_t *) neighbour->prev)->next = neighbour->next; > + neighbour->next->prev = neighbour->prev; > + > + neighbour->slab = NGX_SLAB_PAGE_FREE; > + neighbour->prev = (uintptr_t) &pool->free; > + neighbour->next = &pool->free; > + > + return page; > + } > + return NULL; > +} > + > + > +static ngx_slab_page_t * > ngx_slab_alloc_pages(ngx_slab_pool_t *pool, ngx_uint_t pages) > { > ngx_slab_page_t *page, *p; > @@ -657,6 +677,19 @@ ngx_slab_alloc_pages(ngx_slab_pool_t *po > } > } > > + ngx_flag_t retry = 0; > + for (page = pool->free.next; page != &pool->free;) { > + if (ngx_slab_merge_with_neighbour(pool, page)) { > + retry = 1; > + } else { > + page = page->next; > + } > + } > + > + if (retry) { > + return ngx_slab_alloc_pages(pool, pages); > + } > + > ngx_slab_error(pool, NGX_LOG_CRIT, "ngx_slab_alloc() failed: no memory"); > > return NULL; > @@ -687,6 +720,8 @@ ngx_slab_free_pages(ngx_slab_pool_t *poo > > page->next->prev = (uintptr_t) page; > > pool->free.next = page; > + > + ngx_slab_merge_with_neighbour(pool, page); > } > > > > > > > On Tue, Jul 30, 2013 at 7:09 AM, Maxim Dounin <mdou...@mdounin.ru> wrote: >> >> Hello! >> >> On Mon, Jul 29, 2013 at 04:01:37PM -0300, Wandenberg Peixoto wrote: >> >> [...] >> >> > What would be an alternative to not loop on pool->pages? >> >> Free memory blocks are linked in pool->free list, it should be >> enough to look there. >> >> [...] >> >> -- >> Maxim Dounin >> http://nginx.org/en/donation.html >> >> _______________________________________________ >> nginx-devel mailing list >> nginx-devel@nginx.org >> http://mailman.nginx.org/mailman/listinfo/nginx-devel > > > _______________________________________________ nginx-devel mailing list nginx-devel@nginx.org http://mailman.nginx.org/mailman/listinfo/nginx-devel
