The "fd" field should be after 3 pointers for ngx_event_ident() to use it.
This was broken by ccad84a174e0. While it does not seem to be currently used
for aio-related events, it should be a good idea to preserve the correct
layout nevertheless.
With this change it is now possible to load modules compiled without
the "--with-file-aio" configure option into nginx binary compiled with it,
and vice versa, assuming both use the "--with-compat" option.
This flag appeared in Linux 4.5 and is useful for avoiding thundering herd
problem.
The current Linux kernel implementation walks the list of exclusive waiters,
and queues an event to each epfd, until it finds the first waiter that has
threads blocked on it via epoll_wait().
When it's known that the kernel supports EPOLLRDHUP, there is no need in
additional recv() call to get EOF or error when the flag is absent in the
event generated by the kernel. A special runtime test is done at startup
to detect if EPOLLRDHUP is actually supported by the kernel because
epoll_ctl() silently ignores unknown flags.
With this knowledge it's now possible to drop the "ready" flag for partial
read. Previously, the "ready" flag was kept until the recv() returned EOF
or error. In particular, this change allows the lingering close heuristics
(which relies on the "ready" flag state) to actually work on Linux, and not
wait for more data in most cases.
The "available" flag is now used in the read event with the semantics similar
to the corresponding counter in kqueue.
Fixes various aspects of --test-build-devpoll, --test-build-eventport, and
--test-build-epoll.
In particular, if --test-build-devpoll was used on Linux, then "devpoll"
event method would be preferred over "epoll". Also, wrong definitions of
event macros were chosen.
This reduces layering violation and simplifies the logic of AIO preread, since
it's now triggered by the send chain function itself without falling back to
the copy filter. The context of AIO operation is now stored per file buffer,
which makes it possible to properly handle cases when multiple buffers come
from different locations, each with its own configuration.
In theory, this can provide a bit better distribution of latencies.
Also it simplifies the code, since ngx_queue_t is now used instead
of custom implementation.
And corresponding variable $connections_waiting was added.
Previously, waiting connections were counted as the difference between
active connections and the sum of reading and writing connections.
That made it impossible to count more than one request in one connection
as reading or writing (as is the case for SPDY).
Also, we no longer count connections in handshake state as waiting.
*) Feature: nginx now logs the subrequest information to the error log.
*) Feature: the "proxy_next_upstream", "fastcgi_next_upstream", and
"memcached_next_upstream" directives support the "off" parameter.
*) Feature: the "debug_connection" directive supports the CIDR address
form.
*) Bugfix: if a response of proxied server or FastCGI server was
converted from UTF-8 or back, then it may be transferred incomplete.
*) Bugfix: the $upstream_response_time variable had the time of the
first request to a backend only.
*) Bugfix: nginx could not be built on amd64 platform; the bug had
appeared in 0.3.53.
*) Change: the "variables_hash_max_size" and
"variables_hash_bucket_size" directives.
*) Feature: the $body_bytes_sent variable can be used not only in the
"log_format" directive.
*) Feature: the $ssl_protocol and $ssl_cipher variables.
*) Feature: the cache line size detection for widespread CPUs at start
time.
*) Feature: now the "accept_mutex" directive is supported using
fcntl(2) on platforms different from i386, amd64, sparc64, and ppc.
*) Feature: the "lock_file" directive and the --with-lock-path=PATH
autoconfiguration directive.
*) Bugfix: if the HTTPS protocol was used in the "proxy_pass" directive
then the requests with the body was not transferred.
*) Security: if nginx was built with the ngx_http_realip_module and the
"satisfy_any on" directive was used, then access and authorization
directives did not work. The ngx_http_realip_module was not built
and is not built by default.
*) Change: the "$time_gmt" variable name was changed to "$time_local".
*) Change: the "proxy_header_buffer_size" and
"fastcgi_header_buffer_size" directives was renamed to the
"proxy_buffer_size" and "fastcgi_buffer_size" directives.
*) Feature: the ngx_http_memcached_module.
*) Feature: the "proxy_buffering" directive.
*) Bugfix: the changes in accept mutex handling when the "rtsig" method
was used; the bug had appeared in 0.3.0.
*) Bugfix: if the client sent the "Transfer-Encoding: chunked" header
line, then nginx returns the 411 error.
*) Bugfix: if the "auth_basic" directive was inherited from the http
level, then the realm in the "WWW-Authenticate" header line was
without the "Basic realm" text.
*) Bugfix: if the "combined" format was explicitly specified in the
"access_log" directive, then the empty lines was written to the log;
the bug had appeared in 0.3.8.
*) Bugfix: nginx did not run on the sparc platform under any OS except
Solaris.
*) Bugfix: now it is not necessary to place space between the quoted
string and closing bracket in the "if" directive.
*) Security: nginx now checks URI got from a backend in
"X-Accel-Redirect" header line or in SSI file for the "/../" paths
and zeroes.
*) Change: nginx now does not treat the empty user name in the
"Authorization" header line as valid one.
*) Feature: the "ssl_session_timeout" directives of the
ngx_http_ssl_module and ngx_imap_ssl_module.
*) Feature: the "auth_http_header" directive of the
ngx_imap_auth_http_module.
*) Feature: the "add_header" directive.
*) Feature: the ngx_http_realip_module.
*) Feature: the new variables to use in the "log_format" directive:
$bytes_sent, $apache_bytes_sent, $status, $time_gmt, $uri,
$request_time, $request_length, $upstream_status,
$upstream_response_time, $gzip_ratio, $uid_got, $uid_set,
$connection, $pipe, and $msec. The parameters in the "%name" form
will be canceled soon.
*) Change: now the false variable values in the "if" directive are the
empty string "" and string starting with "0".
*) Bugfix: while using proxied or FastCGI-server nginx may leave
connections and temporary files with client requests in open state.
*) Bugfix: the worker processes did not flush the buffered logs on
graceful exit.
*) Bugfix: if the request URI was changes by the "rewrite" directive
and the request was proxied in location given by regular expression,
then the incorrect request was transferred to backend; the bug had
appeared in 0.2.6.
*) Bugfix: the "expires" directive did not remove the previous
"Expires" header.
*) Bugfix: nginx may stop to accept requests if the "rtsig" method and
several worker processes were used.
*) Bugfix: the "\"" and "\'" escape symbols were incorrectly handled in
SSI commands.
*) Bugfix: if the response was ended just after the SSI command and
gzipping was used, then the response did not transferred complete or
did not transferred at all.
*) Change: the "bl" and "af" parameters of the "listen" directive was
renamed to the "backlog" and "accept_filter".
*) Feature: the "rcvbuf" and "sndbuf" parameters of the "listen"
directive.
*) Change: the "$msec" log parameter does not require now the
additional the gettimeofday() system call.
*) Feature: the -t switch now tests the "listen" directives.
*) Bugfix: if the invalid address was specified in the "listen"
directive, then after the -HUP signal nginx left an open socket in
the CLOSED state.
*) Bugfix: the mime type may be incorrectly set to default value for
index file with variable in the name; the bug had appeared in 0.3.0.
*) Feature: the "timer_resolution" directive.
*) Feature: the millisecond "$upstream_response_time" log parameter.
*) Bugfix: a temporary file with client request body now is removed
just after the response header was transferred to a client.
*) Bugfix: OpenSSL 0.9.6 compatibility.
*) Bugfix: the SSL certificate and key file paths could not be relative.
*) Bugfix: the "ssl_prefer_server_ciphers" directive did not work in
the ngx_imap_ssl_module.
*) Bugfix: the "ssl_protocols" directive allowed to specify the single
protocol only.
*) Bugfix: the segmentation fault occurred when the signal queue
overflowed if the "rtsig" method was used; the bug had appeared in
0.2.0.
*) Change: correct handling of the "\\", "\"", "\'", and "\$" pairs in
SSI.
*) The pid-file names used during online upgrade was changed and now is
not required a manual rename operation. The old master process adds
the ".oldbin" suffix to its pid-file and executes a new binary file.
The new master process creates usual pid-file without the ".newbin"
suffix. If the master process exits, then old master process renames
back its pid-file with the ".oldbin" suffix to the pid-file without
suffix.
*) Change: the "worker_connections" directive, new name of the
"connections" directive; now the directive specifies maximum number
of connections, but not maximum socket descriptor number.
*) Feature: SSL supports the session cache inside one worker process.
*) Feature: the "satisfy_any" directive.
*) Change: the ngx_http_access_module and ngx_http_auth_basic_module do
not run for subrequests.
*) Feature: the "worker_rlimit_nofile" and "worker_rlimit_sigpending"
directives.
*) Bugfix: if all backend using in load-balancing failed after one
error, then nginx did not try do connect to them during 60 seconds.
*) Bugfix: in IMAP/POP3 command argument parsing.
Thanks to Rob Mueller.
*) Bugfix: errors while using SSL in IMAP/POP3 proxy.
*) Bugfix: errors while using SSI and gzipping.
*) Bugfix: the "Expires" and "Cache-Control" header lines were omitted
from the 304 responses.
Thanks to Alexandr Kukushkin.
*) Feature: the ngx_http_ssi_module supports "include virtual" command.
*) Feature: the ngx_http_ssi_module supports the condition command like
'if expr="$NAME"' and "else" and "endif" commands. Only one nested
level is supported.
*) Feature: the ngx_http_ssi_module supports the DATE_LOCAL and
DATE_GMT variables and "config timefmt" command.
*) Feature: the "ssi_ignore_recycled_buffers" directive.
*) Bugfix: the "echo" command did not show the default value for the
empty QUERY_STRING variable.
*) Change: the ngx_http_proxy_module was rewritten.
*) Feature: the "proxy_redirect", "proxy_pass_request_headers",
"proxy_pass_request_body", and "proxy_method" directives.
*) Feature: the "proxy_set_header" directive. The "proxy_x_var" was
canceled and must be replaced with the proxy_set_header directive.
*) Change: the "proxy_preserve_host" is canceled and must be replaced
with the "proxy_set_header Host $host" and the "proxy_redirect off"
directives, the "proxy_set_header Host $host:$proxy_port" directive
and the appropriate proxy_redirect directives.
*) Change: the "proxy_set_x_real_ip" is canceled and must be replaced
with the "proxy_set_header X-Real-IP $remote_addr" directive.
*) Change: the "proxy_add_x_forwarded_for" is canceled and must be
replaced with
the "proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for"
directive.
*) Change: the "proxy_set_x_url" is canceled and must be replaced with
the "proxy_set_header X-URL http://$host:$server_port$request_uri"
directive.
*) Feature: the "fastcgi_param" directive.
*) Change: the "fastcgi_root", "fastcgi_set_var" and "fastcgi_params"
directive are canceled and must be replaced with the fastcgi_param
directives.
*) Feature: the "index" directive can use the variables.
*) Feature: the "index" directive can be used at http and server levels.
*) Change: the last index only in the "index" directive can be absolute.
*) Feature: the "rewrite" directive can use the variables.
*) Feature: the "internal" directive.
*) Feature: the CONTENT_LENGTH, CONTENT_TYPE, REMOTE_PORT, SERVER_ADDR,
SERVER_PORT, SERVER_PROTOCOL, DOCUMENT_ROOT, SERVER_NAME,
REQUEST_METHOD, REQUEST_URI, and REMOTE_USER variables.
*) Change: nginx now passes the invalid lines in a client request
headers or a backend response header.
*) Bugfix: if the backend did not transfer response for a long time and
the "send_timeout" was less than "proxy_read_timeout", then nginx
returned the 408 response.
*) Bugfix: the segmentation fault was occurred if the backend sent an
invalid line in response header; the bug had appeared in 0.1.26.
*) Bugfix: the segmentation fault may occurred in FastCGI fault
tolerance configuration.
*) Bugfix: the "expires" directive did not remove the previous
"Expires" and "Cache-Control" headers.
*) Bugfix: nginx did not take into account trailing dot in "Host"
header line.
*) Bugfix: the ngx_http_auth_module did not work under Linux.
*) Bugfix: the rewrite directive worked incorrectly, if the arguments
were in a request.
*) Bugfix: nginx could not be built on MacOS X.
*) Bugfix: the ngx_http_stub_status_module showed incorrect handled
connections statistics if the proxying or FastCGI server were used.
*) Bugfix: the installation paths were incorrectly quoted on Linux and
Solaris; the bug had appeared in 0.1.21.
*) Bugfix: the proxied request was sent without arguments if the
request contains "//", "/./", "/../" or "%XX".
*) Bugfix: the large compressed responses may be transferred not
completely.
*) Bugfix: the files bigger than 2G was not transferred on Linux that
does not support sendfile64().
*) Bugfix: while the build configuration on Linux the
--with-poll_module parameter was required; the bug had appeared in
0.1.8.
*) Bugfix: in the ngx_http_autoindex_module if the long file names were
in the listing.
*) Feature: the "^~" modifier in the location directive.
*) Feature: the proxy_max_temp_file_size directive.