Mercurial > hg > nginx
view src/http/ngx_http_postpone_filter_module.c @ 7985:ec2e6893caaa
Simplified sendfile(SF_NODISKIO) usage.
Starting with FreeBSD 11, there is no need to use AIO operations to preload
data into cache for sendfile(SF_NODISKIO) to work. Instead, sendfile()
handles non-blocking loading data from disk by itself. It still can, however,
return EBUSY if a page is already being loaded (for example, by a different
process). If this happens, we now post an event for the next event loop
iteration, so sendfile() is retried "after a short period", as manpage
recommends.
The limit of the number of EBUSY tolerated without any progress is preserved,
but now it does not result in an alert, since on an idle system event loop
iteration might be very short and EBUSY can happen many times in a row.
Instead, SF_NODISKIO is simply disabled for one call once the limit is
reached.
With this change, sendfile(SF_NODISKIO) is now used automatically as long as
sendfile() is enabled, and no longer requires "aio on;".
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 27 Dec 2021 19:48:33 +0300 |
parents | 43585e0e12a3 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> static ngx_int_t ngx_http_postpone_filter_add(ngx_http_request_t *r, ngx_chain_t *in); static ngx_int_t ngx_http_postpone_filter_in_memory(ngx_http_request_t *r, ngx_chain_t *in); static ngx_int_t ngx_http_postpone_filter_init(ngx_conf_t *cf); static ngx_http_module_t ngx_http_postpone_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_postpone_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_postpone_filter_module = { NGX_MODULE_V1, &ngx_http_postpone_filter_module_ctx, /* module context */ NULL, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_postpone_filter(ngx_http_request_t *r, ngx_chain_t *in) { ngx_connection_t *c; ngx_http_postponed_request_t *pr; c = r->connection; ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0, "http postpone filter \"%V?%V\" %p", &r->uri, &r->args, in); if (r->subrequest_in_memory) { return ngx_http_postpone_filter_in_memory(r, in); } if (r != c->data) { if (in) { if (ngx_http_postpone_filter_add(r, in) != NGX_OK) { return NGX_ERROR; } return NGX_OK; } #if 0 /* TODO: SSI may pass NULL */ ngx_log_error(NGX_LOG_ALERT, c->log, 0, "http postpone filter NULL inactive request"); #endif return NGX_OK; } if (r->postponed == NULL) { if (in || c->buffered) { return ngx_http_next_body_filter(r->main, in); } return NGX_OK; } if (in) { if (ngx_http_postpone_filter_add(r, in) != NGX_OK) { return NGX_ERROR; } } do { pr = r->postponed; if (pr->request) { ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http postpone filter wake \"%V?%V\"", &pr->request->uri, &pr->request->args); r->postponed = pr->next; c->data = pr->request; return ngx_http_post_request(pr->request, NULL); } if (pr->out == NULL) { ngx_log_error(NGX_LOG_ALERT, c->log, 0, "http postpone filter NULL output"); } else { ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http postpone filter output \"%V?%V\"", &r->uri, &r->args); if (ngx_http_next_body_filter(r->main, pr->out) == NGX_ERROR) { return NGX_ERROR; } } r->postponed = pr->next; } while (r->postponed); return NGX_OK; } static ngx_int_t ngx_http_postpone_filter_add(ngx_http_request_t *r, ngx_chain_t *in) { ngx_http_postponed_request_t *pr, **ppr; if (r->postponed) { for (pr = r->postponed; pr->next; pr = pr->next) { /* void */ } if (pr->request == NULL) { goto found; } ppr = &pr->next; } else { ppr = &r->postponed; } pr = ngx_palloc(r->pool, sizeof(ngx_http_postponed_request_t)); if (pr == NULL) { return NGX_ERROR; } *ppr = pr; pr->request = NULL; pr->out = NULL; pr->next = NULL; found: if (ngx_chain_add_copy(r->pool, &pr->out, in) == NGX_OK) { return NGX_OK; } return NGX_ERROR; } static ngx_int_t ngx_http_postpone_filter_in_memory(ngx_http_request_t *r, ngx_chain_t *in) { size_t len; ngx_buf_t *b; ngx_connection_t *c; ngx_http_core_loc_conf_t *clcf; c = r->connection; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http postpone filter in memory"); if (r->out == NULL) { clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (r->headers_out.content_length_n != -1) { len = r->headers_out.content_length_n; if (len > clcf->subrequest_output_buffer_size) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "too big subrequest response: %uz", len); return NGX_ERROR; } } else { len = clcf->subrequest_output_buffer_size; } b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } b->last_buf = 1; r->out = ngx_alloc_chain_link(r->pool); if (r->out == NULL) { return NGX_ERROR; } r->out->buf = b; r->out->next = NULL; } b = r->out->buf; for ( /* void */ ; in; in = in->next) { if (ngx_buf_special(in->buf)) { continue; } len = in->buf->last - in->buf->pos; if (len > (size_t) (b->end - b->last)) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "too big subrequest response"); return NGX_ERROR; } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http postpone filter in memory %uz bytes", len); b->last = ngx_cpymem(b->last, in->buf->pos, len); in->buf->pos = in->buf->last; } return NGX_OK; } static ngx_int_t ngx_http_postpone_filter_init(ngx_conf_t *cf) { ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_postpone_filter; return NGX_OK; }