http_modules_ngx__http__slice_read_ahead.c The existing slice module (https://nginx.org/en/docs/http/ngx_http_slice_module.html) only starts fetching a given slice whenever bytes in that range for that slice is requested. The patch allows you to configure a variable (slice_read_ahead X) which will cause nginx to start proactively reading X futur…

http_modules_ngx__http__slice_read_ahead.patch

Index: Makefile
===================================================================
--- Makefile	(revision 507358)
+++ Makefile	(revision 507359)
@@ -74,7 +74,7 @@
 	HTTP_CACHE HTTP_DAV HTTP_FLV HTTP_GUNZIP_FILTER HTTP_GZIP_STATIC \
 	HTTP_IMAGE_FILTER HTTP_MP4 HTTP_PERL HTTP_RANDOM_INDEX HTTP_REALIP \
 	HTTP_REWRITE HTTP_SECURE_LINK HTTP_SLICE HTTP_SSL HTTP_STATUS HTTP_SUB \
-	HTTP_XSLT HTTPV2 STREAM STREAM_SSL STREAM_SSL_PREREAD
+	HTTP_XSLT HTTPV2 STREAM STREAM_SSL STREAM_SSL_PREREAD HTTP_SLICE_AHEAD
 # External modules (arrayvar MUST appear after devel_kit for build-dep)
 OPTIONS_GROUP_HTTPGRP+=	AJP AWS_AUTH BROTLI CACHE_PURGE CLOJURE CT DEVEL_KIT \
 	ARRAYVAR DRIZZLE DYNAMIC_UPSTREAM ECHO ENCRYPTSESSION FASTDFS FORMINPUT \
Index: Makefile.extmod
===================================================================
--- Makefile.extmod	(revision 507358)
+++ Makefile.extmod	(revision 507359)
@@ -139,6 +139,8 @@
 HTTP_RESPONSE_DISTFILES=	ngx_http_response-0.3.tar.gz:response
 HTTP_RESPONSE_CONFIGURE_ON=	--add-module=${WRKDIR}/ngx_http_response-0.3
 
+HTTP_SLICE_AHEAD_EXTRA_PATCHES=	${PATCHDIR}/extra-patch-src_http_modules_ngx__http__slice_read_ahead.c
+
 HTTP_SUBS_FILTER_GH_TUPLE=	yaoweibin:ngx_http_substitutions_filter_module:v0.6.4:subs_filter
 HTTP_SUBS_FILTER_CONFIGURE_ON=	--add-module=${WRKSRC_subs_filter}
 
Index: Makefile.options.desc
===================================================================
--- Makefile.options.desc	(revision 507358)
+++ Makefile.options.desc	(revision 507359)
@@ -58,6 +58,7 @@
 HTTP_REWRITE_DESC=		Enable http_rewrite module
 HTTP_SECURE_LINK_DESC=		Enable http_secure_link module
 HTTP_SLICE_DESC=		Enable http_slice module
+HTTP_SLICE_AHEAD=		Enable slice read ahead patch
 HTTP_SSL_DESC=			Enable http_ssl module
 HTTP_STATUS_DESC=		Enable http_stub_status module
 HTTP_SUBS_FILTER_DESC=		3rd party subs filter module
Index: files/extra-patch-src_http_modules_ngx__http__slice_read_ahead.c
===================================================================
--- files/extra-patch-src_http_modules_ngx__http__slice_read_ahead.c	(nonexistent)
+++ files/extra-patch-src_http_modules_ngx__http__slice_read_ahead.c	(revision 507359)
@@ -0,0 +1,456 @@
+--- src/http/modules/ngx_http_slice_filter_module.c.orig	2019-04-23 13:12:58 UTC
++++ src/http/modules/ngx_http_slice_filter_module.c
+@@ -2,6 +2,10 @@
+ /*
+  * Copyright (C) Roman Arutyunyan
+  * Copyright (C) Nginx, Inc.
++ * Copyright (C) Carey Gister
++ * Copyright (C) Metapeer, Inc.
++ *
++ * Retrieve slices with an optional look-a-head of N slices where N is a float value.
+  */
+ 
+ 
+@@ -9,13 +13,25 @@
+ #include <ngx_core.h>
+ #include <ngx_http.h>
+ 
++/*
++ * Location Configuration -- size is size of a slice, read_a_heads is number of
++ * blocks to look a head: 0, will not limit the number of blocks. Blocks will be
++ * retrieved as quickly as GETs can be issued and returned.
++ */
+ 
+ typedef struct {
+     size_t               size;
++    float                read_a_heads;
+ } ngx_http_slice_loc_conf_t;
+ 
+ 
+ typedef struct {
++    size_t               requested_bytes;
++    size_t               received_bytes;
++    size_t               skipped_first_slice;
++} ngx_http_slice_read_a_head_t;
++
++typedef struct {
+     off_t                start;
+     off_t                end;
+     ngx_str_t            range;
+@@ -23,6 +39,7 @@ typedef struct {
+     unsigned             last:1;
+     unsigned             active:1;
+     ngx_http_request_t  *sr;
++    ngx_http_slice_read_a_head_t  *read_a_head;
+ } ngx_http_slice_ctx_t;
+ 
+ 
+@@ -46,6 +63,8 @@ static char *ngx_http_slice_merge_loc_conf(ngx_conf_t 
+     void *child);
+ static ngx_int_t ngx_http_slice_add_variables(ngx_conf_t *cf);
+ static ngx_int_t ngx_http_slice_init(ngx_conf_t *cf);
++static char * ngx_conf_set_float_slot(ngx_conf_t *cf, ngx_command_t *cmd,
++    void *conf);
+ 
+ 
+ static ngx_command_t  ngx_http_slice_filter_commands[] = {
+@@ -57,6 +76,13 @@ static ngx_command_t  ngx_http_slice_filter_commands[]
+       offsetof(ngx_http_slice_loc_conf_t, size),
+       NULL },
+ 
++    { ngx_string("slice_read_ahead"),
++      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
++      ngx_conf_set_float_slot,
++      NGX_HTTP_LOC_CONF_OFFSET,
++      offsetof(ngx_http_slice_loc_conf_t, read_a_heads),
++      NULL },
++
+       ngx_null_command
+ };
+ 
+@@ -102,11 +128,11 @@ static ngx_int_t
+ ngx_http_slice_header_filter(ngx_http_request_t *r)
+ {
+     off_t                            end;
+-    ngx_int_t                        rc;
++    ngx_int_t                        rc, rc1;
+     ngx_table_elt_t                 *h;
+     ngx_http_slice_ctx_t            *ctx;
+     ngx_http_slice_loc_conf_t       *slcf;
+-    ngx_http_slice_content_range_t   cr;
++    ngx_http_slice_content_range_t   cr, cr1;
+ 
+     ctx = ngx_http_get_module_ctx(r, ngx_http_slice_filter_module);
+     if (ctx == NULL) {
+@@ -187,6 +213,23 @@ ngx_http_slice_header_filter(ngx_http_request_t *r)
+     rc = ngx_http_next_header_filter(r);
+ 
+     if (r != r->main) {
++        if (ctx->read_a_head != NULL) {
++            ngx_log_debug5(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (subrequest) requested_bytes: %uz, size: %uz, range: %O/%O, end: %O",
++                ctx->read_a_head->requested_bytes, slcf->size, cr.start,
++                cr.end, end);
++
++            if (end != cr.start) {
++                ctx->read_a_head->requested_bytes +=
++                    ngx_min(slcf->size,
++                        (size_t) end - (size_t) cr.start);
++            }
++
++            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (subrequest) new requested_bytes: %uz, size: %uz",
++                 ctx->read_a_head->requested_bytes, slcf->size);
++        }
++
+         return rc;
+     }
+ 
+@@ -201,8 +244,68 @@ ngx_http_slice_header_filter(ngx_http_request_t *r)
+         ctx->end = r->headers_out.content_offset
+                    + r->headers_out.content_length_n;
+ 
++        /* Update requested bytes for the new chunk. */
++        if (ctx->read_a_head != NULL) {
++            ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (main request, partial) requested_bytes: %uz, size: %uz, start/end (%O/%O)",
++                ctx->read_a_head->requested_bytes, slcf->size,
++                ctx->start, ctx->end);
++
++            if (ctx->end != ctx->start) {
++                ctx->read_a_head->requested_bytes +=
++                    ngx_min(slcf->size,
++                        (size_t) ctx->end - (size_t) ctx->start);
++            }
++
++            ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (main request, partial) new requested_bytes: %uz, size: %uz, start/end (%O/%O)",
++                ctx->read_a_head->requested_bytes, slcf->size, ctx->start, ctx->end);
++
++            /* Parse the new Content-Range, which may have been set by the Range
++               filter. If the start changed, then adjust the requested_byte count
++               by the difference between the slice start and the actual start.
++               These bytes will never be received. */
++
++            rc1 = ngx_http_slice_parse_content_range(r, &cr1);
++            ngx_log_debug(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (main request, partial): rc1: %d",
++                rc1);
++
++            if (rc1 == NGX_OK) {
++                ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                    "http slice header (main request, partial new content range) cr1.start: %uz, cr1.end: %uz",
++                    cr1.start, cr1.end);
++
++                if (cr1.start != cr.start) {
++                    ctx->read_a_head->skipped_first_slice =
++                        cr1.start - (slcf->size * (cr1.start / slcf->size));
++
++                    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                        "http slice header (main request, partial) new cr.start: %uz, initial start: %uz, skipped first slice: %uz",
++                        cr1.start, cr.start,
++                        ctx->read_a_head->skipped_first_slice);
++                }
++            }
++        }
+     } else {
+         ctx->end = cr.complete_length;
++
++        /* Update the requested bytes for the new chunk. */
++        if (ctx->read_a_head != NULL) {
++            ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (main request, full) requested_bytes: %uz, size: %uz, start/end (%O/%O)",
++                ctx->read_a_head->requested_bytes, slcf->size, ctx->start, ctx->end);
++
++            if (ctx->end != ctx->start) {
++                ctx->read_a_head->requested_bytes +=
++                    ngx_min(slcf->size,
++                        (size_t) ctx->end - (size_t) ctx->start);
++            }
++
++            ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice header (main request, full) new requested_bytes: %uz, size: %uz, start/end (%O/%O)",
++                ctx->read_a_head->requested_bytes, slcf->size, ctx->start, ctx->end);
++        }
+     }
+ 
+     return rc;
+@@ -216,14 +319,31 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_
+     ngx_chain_t                *cl;
+     ngx_http_slice_ctx_t       *ctx;
+     ngx_http_slice_loc_conf_t  *slcf;
++    size_t                      received, read_a_head_window, read_a_head_size;
+ 
+     ctx = ngx_http_get_module_ctx(r, ngx_http_slice_filter_module);
+ 
+-    if (ctx == NULL || r != r->main) {
++    if (ctx == NULL) {
+         return ngx_http_next_body_filter(r, in);
+     }
+ 
++    if (r != r->main) {
++        if (ctx->read_a_head != NULL) {
++            received = 0;
++            for (cl = in; cl; cl = cl->next) {
++                received = received + ngx_buf_size(cl->buf);
++            }
++
++            ctx->read_a_head->received_bytes += received;
++        }
++
++        return ngx_http_next_body_filter(r, in);
++    }
++
++    /* For the main request */
++    received = 0;
+     for (cl = in; cl; cl = cl->next) {
++        received = received + ngx_buf_size(cl->buf);
+         if (cl->buf->last_buf) {
+             cl->buf->last_buf = 0;
+             cl->buf->last_in_chain = 1;
+@@ -232,6 +352,10 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_
+         }
+     }
+ 
++    if (ctx->read_a_head != NULL) {
++        ctx->read_a_head->received_bytes += received;
++    }
++
+     rc = ngx_http_next_body_filter(r, in);
+ 
+     if (rc == NGX_ERROR || !ctx->last) {
+@@ -258,6 +382,20 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_
+         return rc;
+     }
+ 
++    slcf = ngx_http_get_module_loc_conf(r, ngx_http_slice_filter_module);
++
++    if (ctx->read_a_head != NULL) {
++        read_a_head_size = (size_t) (slcf->size * slcf->read_a_heads);
++        read_a_head_window = r->connection->sent + read_a_head_size;
++
++        if ((r->connection->sent != 0) &&
++            ((read_a_head_window + ctx->read_a_head->skipped_first_slice) < ctx->read_a_head->requested_bytes)) {
++            ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
++                "http slice body filter defer subrequest: returning NGX_AGAIN");
++            return NGX_AGAIN;
++        }
++    }
++
+     if (ngx_http_subrequest(r, &r->uri, &r->args, &ctx->sr, NULL,
+                             NGX_HTTP_SUBREQUEST_CLONE)
+         != NGX_OK)
+@@ -267,8 +405,6 @@ ngx_http_slice_body_filter(ngx_http_request_t *r, ngx_
+ 
+     ngx_http_set_ctx(ctx->sr, ctx, ngx_http_slice_filter_module);
+ 
+-    slcf = ngx_http_get_module_loc_conf(r, ngx_http_slice_filter_module);
+-
+     ctx->range.len = ngx_sprintf(ctx->range.data, "bytes=%O-%O", ctx->start,
+                                  ctx->start + (off_t) slcf->size - 1)
+                      - ctx->range.data;
+@@ -287,6 +423,7 @@ ngx_http_slice_parse_content_range(ngx_http_request_t 
+     ngx_http_slice_content_range_t *cr)
+ {
+     off_t             start, end, complete_length, cutoff, cutlim;
++    ssize_t           len;
+     u_char           *p;
+     ngx_table_elt_t  *h;
+ 
+@@ -300,6 +437,7 @@ ngx_http_slice_parse_content_range(ngx_http_request_t 
+     }
+ 
+     p = h->value.data + 6;
++    len = h->value.len - 6;
+ 
+     cutoff = NGX_MAX_OFF_T_VALUE / 10;
+     cutlim = NGX_MAX_OFF_T_VALUE % 10;
+@@ -308,56 +446,62 @@ ngx_http_slice_parse_content_range(ngx_http_request_t 
+     end = 0;
+     complete_length = 0;
+ 
+-    while (*p == ' ') { p++; }
++    while ((*p == ' ') && (len != 0)) { p++; len--; }
+ 
+-    if (*p < '0' || *p > '9') {
++    if ((len == 0) || (*p < '0' || *p > '9')) {
+         return NGX_ERROR;
+     }
+ 
+-    while (*p >= '0' && *p <= '9') {
++    while ((len != 0) && (*p >= '0' && *p <= '9')) {
+         if (start >= cutoff && (start > cutoff || *p - '0' > cutlim)) {
+             return NGX_ERROR;
+         }
+ 
+         start = start * 10 + (*p++ - '0');
++        len--;
+     }
+ 
+-    while (*p == ' ') { p++; }
++    while ((len != 0) && (*p == ' ')) { p++; len--; }
+ 
+-    if (*p++ != '-') {
++    if ((len == 0) || (*p++ != '-')) {
+         return NGX_ERROR;
+     }
+ 
+-    while (*p == ' ') { p++; }
++    len--;
+ 
+-    if (*p < '0' || *p > '9') {
++    while ((len != 0) && (*p == ' ')) { p++; len--; }
++
++    if ((len == 0) || (*p < '0' || *p > '9')) {
+         return NGX_ERROR;
+     }
+ 
+-    while (*p >= '0' && *p <= '9') {
++    while ((len != 0) && (*p >= '0' && *p <= '9')) {
+         if (end >= cutoff && (end > cutoff || *p - '0' > cutlim)) {
+             return NGX_ERROR;
+         }
+ 
+         end = end * 10 + (*p++ - '0');
++        len--;
+     }
+ 
+     end++;
+ 
+-    while (*p == ' ') { p++; }
++    while ((len != 0) && (*p == ' ')) { p++; len--; }
+ 
+-    if (*p++ != '/') {
++    if ((len == 0) || (*p++ != '/')) {
+         return NGX_ERROR;
+     }
+ 
+-    while (*p == ' ') { p++; }
++    len--;
+ 
+-    if (*p != '*') {
++    while ((len != 0) && (*p == ' ')) { p++; len--; }
++
++    if ((len != 0) && (*p != '*')) {
+         if (*p < '0' || *p > '9') {
+             return NGX_ERROR;
+         }
+ 
+-        while (*p >= '0' && *p <= '9') {
++        while ((len != 0) && (*p >= '0' && *p <= '9')) {
+             if (complete_length >= cutoff
+                 && (complete_length > cutoff || *p - '0' > cutlim))
+             {
+@@ -365,16 +509,18 @@ ngx_http_slice_parse_content_range(ngx_http_request_t 
+             }
+ 
+             complete_length = complete_length * 10 + (*p++ - '0');
++            len--;
+         }
+ 
+     } else {
+         complete_length = -1;
+         p++;
++        len--;
+     }
+ 
+-    while (*p == ' ') { p++; }
++    while ((len != 0) && (*p == ' ')) { p++; len--; }
+ 
+-    if (*p != '\0') {
++    if (len != 0) {
+         return NGX_ERROR;
+     }
+ 
+@@ -390,9 +536,10 @@ static ngx_int_t
+ ngx_http_slice_range_variable(ngx_http_request_t *r,
+     ngx_http_variable_value_t *v, uintptr_t data)
+ {
+-    u_char                     *p;
+-    ngx_http_slice_ctx_t       *ctx;
+-    ngx_http_slice_loc_conf_t  *slcf;
++    u_char                        *p;
++    ngx_http_slice_ctx_t          *ctx;
++    ngx_http_slice_loc_conf_t     *slcf;
++    ngx_http_slice_read_a_head_t  *read_a_head;
+ 
+     ctx = ngx_http_get_module_ctx(r, ngx_http_slice_filter_module);
+ 
+@@ -414,6 +561,15 @@ ngx_http_slice_range_variable(ngx_http_request_t *r,
+             return NGX_ERROR;
+         }
+ 
++        if (slcf->read_a_heads != 0.0) {
++            read_a_head = ngx_pcalloc(r->pool, sizeof(ngx_http_slice_read_a_head_t));
++            if (read_a_head == NULL) {
++                return NGX_ERROR;
++            }
++
++            ctx->read_a_head = read_a_head;
++        }
++
+         ngx_http_set_ctx(r, ctx, ngx_http_slice_filter_module);
+ 
+         p = ngx_pnalloc(r->pool, sizeof("bytes=-") - 1 + 2 * NGX_OFF_T_LEN);
+@@ -488,6 +644,39 @@ ngx_http_slice_get_start(ngx_http_request_t *r)
+ }
+ 
+ 
++static char *
++ngx_conf_set_float_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
++{
++    char             *p = conf;
++    float            *np;
++    ngx_str_t        *value;
++    ngx_conf_post_t  *post;
++    ngx_int_t        val;
++
++    np = (float *) (p + cmd->offset);
++
++    if (*np != (float) NGX_CONF_UNSET) {
++        return "is duplicate";
++    }
++
++    value = cf->args->elts;
++    val = ngx_atofp(value[1].data, value[1].len, 3);
++
++    *np = (float) val / 1000.0;
++
++    if (*np == (float) NGX_ERROR) {
++        return "invalid number";
++    }
++
++    if (cmd->post) {
++        post = cmd->post;
++        return post->post_handler(cf, post, np);
++    }
++
++    return NGX_CONF_OK;
++}
++
++
+ static void *
+ ngx_http_slice_create_loc_conf(ngx_conf_t *cf)
+ {
+@@ -499,6 +688,7 @@ ngx_http_slice_create_loc_conf(ngx_conf_t *cf)
+     }
+ 
+     slcf->size = NGX_CONF_UNSET_SIZE;
++    slcf->read_a_heads = (float) NGX_CONF_UNSET;
+ 
+     return slcf;
+ }
+@@ -511,6 +701,13 @@ ngx_http_slice_merge_loc_conf(ngx_conf_t *cf, void *pa
+     ngx_http_slice_loc_conf_t *conf = child;
+ 
+     ngx_conf_merge_size_value(conf->size, prev->size, 0);
++    ngx_conf_merge_value(conf->read_a_heads, prev->read_a_heads, 0.0);
++
++    if (conf->read_a_heads < 0.0) {
++        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "read a head must be >= 0");
++        return NGX_CONF_ERROR;
++    }
++
+ 
+     return NGX_CONF_OK;
+ }

Property changes on: files/extra-patch-src_http_modules_ngx__http__slice_read_ahead.c
___________________________________________________________________
Added: fbsd:nokeywords
## -0,0 +1 ##
+yes
\ No newline at end of property
Added: svn:eol-style
## -0,0 +1 ##
+native
\ No newline at end of property
Added: svn:mime-type
## -0,0 +1 ##
+text/plain
\ No newline at end of property