Age | Commit message (Collapse) | Author |
|
This improves the latency of file operations as dirty schedulers
are a bit more eager to run jobs than async threads, and use a
single global queue rather than per-thread queues, eliminating the
risk of a job stalling behind a long-running job on the same thread
while other async threads sit idle.
There's no such thing as a free lunch though; the lowered latency
comes at the cost of increased busy-waiting which may have an
adverse effect on some applications. This behavior can be tweaked
with the +sbwt flag, but unfortunately it affects all types of
schedulers and not just dirty ones. We plan to add type-specific
flags at a later stage.
sendfile has been moved to inet_drv to lessen the effect of a nasty
race; the cooperation between inet_drv and efile has never been
airtight and the socket dying at the wrong time (Regardless of
reason) could result in fd aliasing. Moving it to the inet driver
makes it impossible to trigger this by closing the socket in the
middle of a sendfile operation, while still allowing it to be
aborted -- something that can't be done if it stays in the file
driver.
The race still occurs if the controlling process dies in the short
window between dispatching the sendfile operation and the dup(2)
call in the driver, but it's much less likely to happen now.
A proper fix is in the works.
--
Notable functional differences:
* The use_threads option for file:sendfile/5 no longer has any
effect.
* The file-specific DTrace probes have been removed. The same
effect can be achieved with normal tracing together with the
nif__entry/nif__return probes to track scheduling.
--
OTP-14256
|
|
|
|
bind to device is needed to properly support VRF-Lite under
Linux (see [1] for details).
[1]: https://www.kernel.org/doc/Documentation/networking/vrf.txt
|
|
|
|
|
|
|
|
|
|
When a AF_LOCAL file descriptor is created externally (e.g. Unix
Domain Socket) and passed to `gen_tcp:listen(0, [{fd, FD}])`, the
implementation incorrectly assigned the address family to be equal
to `inet`, which in the inet_drv driver translated to AF_INET instead
of AF_LOCAL (or AF_UNIX), and an `einval` error code was returned.
This patch fixes this problem such that the file descriptors of the
`local` address family are supported in the inet:fdopen/5,
gen_tcp:connect/3, gen_tcp:listen/2, gen_udp:open/2 calls
|
|
A new {line_delimiter, byte()} option allows line-oriented TCP-based
protocols to use a custom line delimiting character. It is to be
used in conjunction with {packet, line}.
This option also works with erlang:decode_packet/3 when its first argument
is 'line'.
|
|
|
|
An ECONNRESET is a socket error which tells us that a TCP peer has sent
an RST. The RST indicates that they have aborted the connection and
that the payload we have received should not be considered complete. Up
until now, the implementation of TCP in inet_drv.c has hidden the
receipt of the RST from the user, treating it as though it was just
a FIN terminating the read side of the socket.
There are many cases where user code needs to be able to distinguish
between a socket that was closed normally and one that was aborted.
Setting the option {show_econnreset, true} enables the user to receive
ECONNRESET errors on both active and passive sockets.
A connected socket returned from gen_tcp:accept/1 will inherit the
show_econnreset setting of the listening socket.
By default this option is set to {show_econnreset, false}.
Note that this patch only enables the reporting of ECONNRESET when
the socket is being read from. It does not report ECONNRESET (or
EPIPE) when the user tries to write to a connection when an RST
has already been received. Currently the TCP implementation in
inet_drv.c hides all such send errors from the user in favour
of returning {error, close}. A separate patch will be needed to
enable the reporting of such errors.
|
|
Conflicts:
erts/preloaded/ebin/prim_inet.beam
lib/kernel/test/gen_sctp_SUITE.erl
|
|
|
|
Add the {active,N} socket option, where N is an integer in the range
-32768..32767, to allow a caller to specify the number of data messages to
be delivered to the controlling process. Once the socket's delivered
message count either reaches 0 or is explicitly set to 0 with
inet:setopts/2 or by including {active,0} as an option when the socket is
created, the socket transitions to passive ({active, false}) mode and the
socket's controlling process receives a message to inform it of the
transition. TCP sockets receive {tcp_passive,Socket}, UDP sockets receive
{udp_passive,Socket} and SCTP sockets receive {sctp_passive,Socket}.
The socket's delivered message counter defaults to 0, but it can be set
using {active,N} via any gen_tcp, gen_udp, or gen_sctp function that takes
socket options as arguments, or via inet:setopts/2. New N values are added
to the socket's current counter value, and negative numbers can be used to
reduce the counter value. Specifying a number that would cause the socket's
counter value to go above 32767 causes an einval error. If a negative
number is specified such that the counter value would become negative, the
socket's counter value is set to 0 and the socket transitions to passive
mode. If the counter value is already 0 and inet:setopts(Socket,
[{active,0}]) is specified, the counter value remains at 0 but the
appropriate passive mode transition message is generated for the socket.
This commit contains a modified preloaded prim_inet.beam due to changes in
prim_inet.erl.
Add tests for {active,N} mode for TCP, UDP, and SCTP sockets.
Add documentation for {active,N} mode for inet, gen_tcp, gen_udp, and
gen_sctp.
|
|
|
|
|
|
|
|
rickard/r16/port-optimizations/OTP-10336
* rickard/port-optimizations/OTP-10336:
Change annotate level for emacs-22 in cerl
Update etp-commands
Add documentation on communication in Erlang
Add support for busy port message queue
Add driver callback epilogue
Implement true asynchronous signaling between processes and ports
Add erl_drv_[send|output]_term
Move busy port flag
Use rwlock for driver list
Optimize management of port tasks
Improve configuration of process and port tables
Remove R9 compatibility features
Use ptab functionality also for ports
Prepare for use of ptab functionality also for ports
Atomic port state
Generalize process table implementation
Implement functionality for delaying thread progress from unmanaged threads
Conflicts:
erts/doc/src/erl_driver.xml
erts/doc/src/erlang.xml
erts/emulator/beam/beam_bif_load.c
erts/emulator/beam/beam_bp.c
erts/emulator/beam/beam_emu.c
erts/emulator/beam/bif.c
erts/emulator/beam/copy.c
erts/emulator/beam/erl_alloc.c
erts/emulator/beam/erl_alloc.types
erts/emulator/beam/erl_bif_info.c
erts/emulator/beam/erl_bif_port.c
erts/emulator/beam/erl_bif_trace.c
erts/emulator/beam/erl_init.c
erts/emulator/beam/erl_message.c
erts/emulator/beam/erl_port_task.c
erts/emulator/beam/erl_process.c
erts/emulator/beam/erl_process.h
erts/emulator/beam/erl_process_lock.c
erts/emulator/beam/erl_trace.c
erts/emulator/beam/export.h
erts/emulator/beam/global.h
erts/emulator/beam/io.c
erts/emulator/sys/unix/sys.c
erts/emulator/sys/vxworks/sys.c
erts/emulator/test/port_SUITE.erl
erts/etc/unix/cerl.src
erts/preloaded/ebin/erlang.beam
erts/preloaded/ebin/prim_inet.beam
erts/preloaded/src/prim_inet.erl
lib/hipe/cerl/erl_bif_types.erl
lib/kernel/doc/src/inet.xml
lib/kernel/src/inet.erl
|
|
|
|
|
|
|
|
Ignore fd is a feature used by sendfile to temporarily remove
all driver_select calls on that fd so that another driver can
select on it. It also delays all actions which sends or receives
data in that fd until in the fd is no longer ignored.
Only the controlling_process should use the feature as it is otherwise
possible that the ignore will never be cleaned up and hence create
a memory leak in the driver.
An ignored driver will not detect that an fd has been closed until
it is unignored.
|
|
|
|
|
|
|
|
|
|
|