From: Eric Wong <e@80x24.org>
To: kgio-public@bogomips.org
Cc: Eric Wong <e@80x24.org>
Subject: [PATCH] remove autopush support and make it a no-op
Date: Thu, 13 Aug 2015 20:55:39 +0000 [thread overview]
Message-ID: <1439499339-29222-1-git-send-email-e@80x24.org> (raw)
Maintaining global state in a library like kgio is ugly, and it
is not optimal from a performance standpoint compared to using
MSG_MORE.
TCP_CORK and TCP_NOPUSH require extra syscalls so it still offers
sub-optimal performance compared to MSG_MORE.
Instead, server developers should use MSG_MORE if their OS supports
it (and should add MSG_MORE to their OS if lacking it).
---
.document | 1 -
ext/kgio/accept.c | 7 --
ext/kgio/autopush.c | 247 --------------------------------------------------
ext/kgio/kgio.h | 12 ---
ext/kgio/kgio_ext.c | 1 -
ext/kgio/read.c | 8 --
ext/kgio/write.c | 4 -
ext/kgio/writev.c | 2 -
lib/kgio.rb | 10 ++
test/test_autopush.rb | 160 +-------------------------------
10 files changed, 13 insertions(+), 439 deletions(-)
delete mode 100644 ext/kgio/autopush.c
diff --git a/.document b/.document
index c7e09c6..f3a0872 100644
--- a/.document
+++ b/.document
@@ -7,7 +7,6 @@ ISSUES
HACKING
lib
ext/kgio/accept.c
-ext/kgio/autopush.c
ext/kgio/connect.c
ext/kgio/kgio_ext.c
ext/kgio/poll.c
diff --git a/ext/kgio/accept.c b/ext/kgio/accept.c
index c847c92..4a45e2f 100644
--- a/ext/kgio/accept.c
+++ b/ext/kgio/accept.c
@@ -160,12 +160,6 @@ static VALUE in_addr_set(VALUE io, struct sockaddr_storage *addr, socklen_t len)
return rb_ivar_set(io, iv_kgio_addr, host);
}
-#if defined(__linux__)
-# define post_accept kgio_autopush_accept
-#else
-# define post_accept(a,b) for(;0;)
-#endif
-
static VALUE
my_accept(struct accept_args *a, int force_nonblock)
{
@@ -211,7 +205,6 @@ retry:
}
}
client_io = sock_for_fd(a->accepted_class, client_fd);
- post_accept(a->accept_io, client_io);
if (a->addr)
in_addr_set(client_io,
diff --git a/ext/kgio/autopush.c b/ext/kgio/autopush.c
deleted file mode 100644
index 74576e8..0000000
--- a/ext/kgio/autopush.c
+++ /dev/null
@@ -1,247 +0,0 @@
-/*
- * We use a very basic strategy to use TCP_CORK semantics optimally
- * in most TCP servers: On corked sockets, we will uncork on recv()
- * if there was a previous send(). Otherwise we do not fiddle
- * with TCP_CORK at all.
- *
- * Under Linux, we can rely on TCP_CORK being inherited in an
- * accept()-ed client socket so we can avoid syscalls for each
- * accept()-ed client if we know the accept() socket corks.
- *
- * This module does NOTHING for client TCP sockets, we only deal
- * with accept()-ed sockets right now.
- */
-
-#include "kgio.h"
-#include "my_fileno.h"
-#include <netinet/tcp.h>
-
-/*
- * As of FreeBSD 4.5, TCP_NOPUSH == TCP_CORK
- * ref: http://dotat.at/writing/nopush.html
- * We won't care for older FreeBSD since nobody runs Ruby on them...
- */
-#ifdef TCP_CORK
-# define KGIO_NOPUSH TCP_CORK
-#elif defined(TCP_NOPUSH)
-# define KGIO_NOPUSH TCP_NOPUSH
-#endif
-
-#ifdef KGIO_NOPUSH
-static ID id_autopush_state;
-static int enabled = 1;
-
-enum autopush_state {
- AUTOPUSH_STATE_ACCEPTOR_IGNORE = -1,
- AUTOPUSH_STATE_IGNORE = 0,
- AUTOPUSH_STATE_WRITER = 1,
- AUTOPUSH_STATE_WRITTEN = 2,
- AUTOPUSH_STATE_ACCEPTOR = 3
-};
-
-#if defined(R_CAST) && \
- defined(HAVE_TYPE_STRUCT_RFILE) && \
- defined(HAVE_TYPE_STRUCT_ROBJECT) && \
- ((SIZEOF_STRUCT_RFILE + SIZEOF_INT) <= (SIZEOF_STRUCT_ROBJECT))
-
-struct AutopushSocket {
- struct RFile rfile;
- enum autopush_state autopush_state;
-};
-
-static enum autopush_state state_get(VALUE io)
-{
- return ((struct AutopushSocket *)(io))->autopush_state;
-}
-
-static void state_set(VALUE io, enum autopush_state state)
-{
- ((struct AutopushSocket *)(io))->autopush_state = state;
-}
-#else
-static enum autopush_state state_get(VALUE io)
-{
- VALUE val;
-
- if (rb_ivar_defined(io, id_autopush_state) == Qfalse)
- return AUTOPUSH_STATE_IGNORE;
- val = rb_ivar_get(io, id_autopush_state);
-
- return (enum autopush_state)NUM2INT(val);
-}
-
-static void state_set(VALUE io, enum autopush_state state)
-{
- rb_ivar_set(io, id_autopush_state, INT2NUM(state));
-}
-#endif /* IVAR fallback */
-
-static enum autopush_state detect_acceptor_state(VALUE io);
-static void push_pending_data(VALUE io);
-
-/*
- * call-seq:
- * Kgio.autopush? -> true or false
- *
- * Returns whether or not autopush is enabled.
- *
- * Only available on systems with TCP_CORK (Linux) or
- * TCP_NOPUSH (FreeBSD, and maybe other *BSDs).
- */
-static VALUE s_get_autopush(VALUE self)
-{
- return enabled ? Qtrue : Qfalse;
-}
-
-/*
- * call-seq:
- * Kgio.autopush = true
- * Kgio.autopush = false
- *
- * Enables or disables autopush for sockets created with kgio_accept
- * and kgio_tryaccept methods. Autopush relies on TCP_CORK/TCP_NOPUSH
- * being enabled on the listen socket.
- *
- * Only available on systems with TCP_CORK (Linux) or
- * TCP_NOPUSH (FreeBSD, and maybe other *BSDs).
- */
-static VALUE s_set_autopush(VALUE self, VALUE val)
-{
- enabled = RTEST(val);
-
- return val;
-}
-
-/*
- * call-seq:
- *
- * io.kgio_autopush? -> true or false
- *
- * Returns the current autopush state of the Kgio::SocketMethods-enabled
- * socket.
- *
- * Only available on systems with TCP_CORK (Linux) or
- * TCP_NOPUSH (FreeBSD, and maybe other *BSDs).
- */
-static VALUE autopush_get(VALUE io)
-{
- return state_get(io) <= 0 ? Qfalse : Qtrue;
-}
-
-/*
- * call-seq:
- *
- * io.kgio_autopush = true
- * io.kgio_autopush = false
- *
- * Enables or disables autopush on any given Kgio::SocketMethods-capable
- * IO object. This does NOT enable or disable TCP_NOPUSH/TCP_CORK right
- * away, that must be done with IO.setsockopt
- *
- * Only available on systems with TCP_CORK (Linux) or
- * TCP_NOPUSH (FreeBSD, and maybe other *BSDs).
- */
-static VALUE autopush_set(VALUE io, VALUE vbool)
-{
- if (RTEST(vbool))
- state_set(io, AUTOPUSH_STATE_WRITER);
- else
- state_set(io, AUTOPUSH_STATE_IGNORE);
- return vbool;
-}
-
-void init_kgio_autopush(void)
-{
- VALUE mKgio = rb_define_module("Kgio");
- VALUE tmp;
-
- rb_define_singleton_method(mKgio, "autopush?", s_get_autopush, 0);
- rb_define_singleton_method(mKgio, "autopush=", s_set_autopush, 1);
-
- tmp = rb_define_module_under(mKgio, "SocketMethods");
- rb_define_method(tmp, "kgio_autopush=", autopush_set, 1);
- rb_define_method(tmp, "kgio_autopush?", autopush_get, 0);
-
- id_autopush_state = rb_intern("@kgio_autopush_state");
-}
-
-/*
- * called after a successful write, just mark that we've put something
- * in the skb and will need to uncork on the next write.
- */
-void kgio_autopush_send(VALUE io)
-{
- if (state_get(io) == AUTOPUSH_STATE_WRITER)
- state_set(io, AUTOPUSH_STATE_WRITTEN);
-}
-
-/* called on successful accept() */
-void kgio_autopush_accept(VALUE accept_io, VALUE client_io)
-{
- enum autopush_state acceptor_state;
-
- if (!enabled)
- return;
- acceptor_state = state_get(accept_io);
- if (acceptor_state == AUTOPUSH_STATE_IGNORE)
- acceptor_state = detect_acceptor_state(accept_io);
- if (acceptor_state == AUTOPUSH_STATE_ACCEPTOR)
- state_set(client_io, AUTOPUSH_STATE_WRITER);
- else
- state_set(client_io, AUTOPUSH_STATE_IGNORE);
-}
-
-void kgio_autopush_recv(VALUE io)
-{
- if (enabled && (state_get(io) == AUTOPUSH_STATE_WRITTEN)) {
- push_pending_data(io);
- state_set(io, AUTOPUSH_STATE_WRITER);
- }
-}
-
-static enum autopush_state detect_acceptor_state(VALUE io)
-{
- int corked = 0;
- int fd = my_fileno(io);
- socklen_t optlen = sizeof(int);
- enum autopush_state state;
-
- if (getsockopt(fd, IPPROTO_TCP, KGIO_NOPUSH, &corked, &optlen) != 0) {
- if (errno != EOPNOTSUPP)
- rb_sys_fail("getsockopt(TCP_CORK/TCP_NOPUSH)");
- errno = 0;
- state = AUTOPUSH_STATE_ACCEPTOR_IGNORE;
- } else if (corked) {
- state = AUTOPUSH_STATE_ACCEPTOR;
- } else {
- state = AUTOPUSH_STATE_ACCEPTOR_IGNORE;
- }
- state_set(io, state);
-
- return state;
-}
-
-/*
- * checks to see if we've written anything since the last recv()
- * If we have, uncork the socket and immediately recork it.
- */
-static void push_pending_data(VALUE io)
-{
- int optval = 0;
- const socklen_t optlen = sizeof(int);
- const int fd = my_fileno(io);
-
- if (setsockopt(fd, IPPROTO_TCP, KGIO_NOPUSH, &optval, optlen) != 0)
- rb_sys_fail("setsockopt(TCP_CORK/TCP_NOPUSH, 0)");
- /* immediately recork */
- optval = 1;
- if (setsockopt(fd, IPPROTO_TCP, KGIO_NOPUSH, &optval, optlen) != 0)
- rb_sys_fail("setsockopt(TCP_CORK/TCP_NOPUSH, 1)");
-}
-#else /* !KGIO_NOPUSH */
-void kgio_autopush_recv(VALUE io){}
-void kgio_autopush_send(VALUE io){}
-void init_kgio_autopush(void)
-{
-}
-#endif /* ! KGIO_NOPUSH */
diff --git a/ext/kgio/kgio.h b/ext/kgio/kgio.h
index c0630ae..a3f2f66 100644
--- a/ext/kgio/kgio.h
+++ b/ext/kgio/kgio.h
@@ -29,14 +29,9 @@ void init_kgio_write(void);
void init_kgio_writev(void);
void init_kgio_accept(void);
void init_kgio_connect(void);
-void init_kgio_autopush(void);
void init_kgio_poll(void);
void init_kgio_tryopen(void);
-void kgio_autopush_accept(VALUE, VALUE);
-void kgio_autopush_recv(VALUE);
-void kgio_autopush_send(VALUE);
-
VALUE kgio_call_wait_writable(VALUE io);
VALUE kgio_call_wait_readable(VALUE io);
#if defined(HAVE_RB_THREAD_CALL_WITHOUT_GVL) && defined(HAVE_RUBY_THREAD_H)
@@ -90,13 +85,6 @@ NORETURN(void kgio_rd_sys_fail(const char *));
# define USE_MSG_DONTWAIT
# endif
-#ifdef USE_MSG_DONTWAIT
-/* we don't need these variants, we call kgio_autopush_send/recv directly */
-static inline void kgio_autopush_write(VALUE io) { }
-#else
-static inline void kgio_autopush_write(VALUE io) { kgio_autopush_send(io); }
-#endif
-
/* prefer rb_str_subseq because we don't use negative offsets */
#ifndef HAVE_RB_STR_SUBSEQ
#define MY_STR_SUBSEQ(str,beg,len) rb_str_substr((str),(beg),(len))
diff --git a/ext/kgio/kgio_ext.c b/ext/kgio/kgio_ext.c
index 8829eae..c3e59ec 100644
--- a/ext/kgio/kgio_ext.c
+++ b/ext/kgio/kgio_ext.c
@@ -95,7 +95,6 @@ void Init_kgio_ext(void)
init_kgio_writev();
init_kgio_connect();
init_kgio_accept();
- init_kgio_autopush();
init_kgio_poll();
init_kgio_tryopen();
}
diff --git a/ext/kgio/read.c b/ext/kgio/read.c
index 472a592..e55db16 100644
--- a/ext/kgio/read.c
+++ b/ext/kgio/read.c
@@ -7,13 +7,8 @@ static VALUE sym_wait_readable;
#ifdef USE_MSG_DONTWAIT
static const int peek_flags = MSG_DONTWAIT|MSG_PEEK;
-
-/* we don't need these variants, we call kgio_autopush_recv directly */
-static inline void kgio_autopush_read(VALUE io) { }
-
#else
static const int peek_flags = MSG_PEEK;
-static inline void kgio_autopush_read(VALUE io) { kgio_autopush_recv(io); }
#endif
struct rd_args {
@@ -85,7 +80,6 @@ static VALUE my_read(int io_wait, int argc, VALUE *argv, VALUE io)
long n;
prepare_read(&a, argc, argv, io);
- kgio_autopush_read(io);
if (a.len > 0) {
set_nonblocking(a.fd);
@@ -158,7 +152,6 @@ static VALUE my_recv(int io_wait, int argc, VALUE *argv, VALUE io)
long n;
prepare_read(&a, argc, argv, io);
- kgio_autopush_recv(io);
if (a.len > 0) {
retry:
@@ -212,7 +205,6 @@ static VALUE my_peek(int io_wait, int argc, VALUE *argv, VALUE io)
long n;
prepare_read(&a, argc, argv, io);
- kgio_autopush_recv(io);
if (a.len > 0) {
if (peek_flags == MSG_PEEK)
diff --git a/ext/kgio/write.c b/ext/kgio/write.c
index ce4aa75..fa0d53c 100644
--- a/ext/kgio/write.c
+++ b/ext/kgio/write.c
@@ -72,8 +72,6 @@ retry:
n = (long)write(a.fd, a.ptr, a.len);
if (write_check(&a, n, "write", io_wait) != 0)
goto retry;
- if (TYPE(a.buf) != T_SYMBOL)
- kgio_autopush_write(io);
return a.buf;
}
@@ -126,8 +124,6 @@ retry:
n = (long)send(a.fd, a.ptr, a.len, MSG_DONTWAIT);
if (write_check(&a, n, "send", io_wait) != 0)
goto retry;
- if (TYPE(a.buf) != T_SYMBOL)
- kgio_autopush_send(io);
return a.buf;
}
diff --git a/ext/kgio/writev.c b/ext/kgio/writev.c
index d3ec53e..736aa6f 100644
--- a/ext/kgio/writev.c
+++ b/ext/kgio/writev.c
@@ -249,8 +249,6 @@ static VALUE my_writev(VALUE io, VALUE ary, int io_wait)
} while (writev_check(&a, n, "writev", io_wait) != 0);
rb_str_resize(a.vec_buf, 0);
- if (TYPE(a.buf) != T_SYMBOL)
- kgio_autopush_write(io);
return a.buf;
}
diff --git a/lib/kgio.rb b/lib/kgio.rb
index 5de431b..f192074 100644
--- a/lib/kgio.rb
+++ b/lib/kgio.rb
@@ -16,6 +16,16 @@ module Kgio
# PipeMethods#kgio_trywrite and SocketMethods#kgio_trywrite will return
# :wait_writable when waiting for a read is required.
WaitWritable = :wait_writable
+
+ # autopush is no-op nowadays
+ @autopush = false
+
+ class << self
+ attr_accessor :autopush # :nodoc:
+ def autopush? # :nodoc:
+ !!@autopush
+ end
+ end
end
require 'kgio_ext'
diff --git a/test/test_autopush.rb b/test/test_autopush.rb
index 38b7c52..4e5af92 100644
--- a/test/test_autopush.rb
+++ b/test/test_autopush.rb
@@ -1,165 +1,11 @@
-require 'tempfile'
require 'test/unit'
-begin
- $-w = false
- RUBY_PLATFORM =~ /linux/ and require 'strace'
-rescue LoadError
-end
-$-w = true
require 'kgio'
class TestAutopush < Test::Unit::TestCase
- TCP_CORK = 3
- TCP_NOPUSH = 4
-
- def setup
- Kgio.autopush = false
- assert_equal false, Kgio.autopush?
-
- @host = ENV["TEST_HOST"] || '127.0.0.1'
- @srv = Kgio::TCPServer.new(@host, 0)
- RUBY_PLATFORM =~ /linux/ and
- @srv.setsockopt(Socket::IPPROTO_TCP, TCP_CORK, 1)
- RUBY_PLATFORM =~ /freebsd/ and
- @srv.setsockopt(Socket::IPPROTO_TCP, TCP_NOPUSH, 1)
- @port = @srv.addr[1]
- end
-
- def test_autopush_accessors
- Kgio.autopush = true
- opt = RUBY_PLATFORM =~ /freebsd/ ? TCP_NOPUSH : TCP_CORK
- s = Kgio::TCPSocket.new(@host, @port)
- assert_equal 0, s.getsockopt(Socket::IPPROTO_TCP, opt).unpack('i')[0]
- assert ! s.kgio_autopush?
- s.kgio_autopush = true
- assert s.kgio_autopush?
- s.kgio_write 'asdf'
- assert_equal :wait_readable, s.kgio_tryread(1)
- assert s.kgio_autopush?
- val = s.getsockopt(Socket::IPPROTO_TCP, opt).unpack('i')[0]
- assert_operator val, :>, 0, "#{opt}=#{val} (#{RUBY_PLATFORM})"
- end
-
- def test_autopush_true_unix
- Kgio.autopush = true
- tmp = Tempfile.new('kgio_unix')
- @path = tmp.path
- tmp.close!
- @srv = Kgio::UNIXServer.new(@path)
- @rd = Kgio::UNIXSocket.new(@path)
- t0 = nil
- if defined?(Strace)
- io, err = Strace.me { @wr = @srv.kgio_accept }
- assert_nil err
- rc = nil
- io, err = Strace.me {
- t0 = Time.now
- @wr.kgio_write "HI\n"
- rc = @wr.kgio_tryread 666
- }
- assert_nil err
- lines = io.readlines
- assert lines.grep(/TCP_CORK/).empty?, lines.inspect
- else
- @wr = @srv.kgio_accept
- t0 = Time.now
- @wr.kgio_write "HI\n"
- rc = @wr.kgio_tryread 666
- end
- assert_equal "HI\n", @rd.kgio_read(3)
- diff = Time.now - t0
- assert(diff < 0.200, "nopush on UNIX sockets? diff=#{diff} > 200ms")
- assert_equal :wait_readable, rc
- ensure
- File.unlink(@path) rescue nil
- end
-
- def test_autopush_false
- Kgio.autopush = nil
- assert_equal false, Kgio.autopush?
-
- @wr = Kgio::TCPSocket.new(@host, @port)
- if defined?(Strace)
- io, err = Strace.me { @rd = @srv.kgio_accept }
- assert_nil err
- lines = io.readlines
- assert lines.grep(/TCP_CORK/).empty?, lines.inspect
- assert_equal 1, @rd.getsockopt(Socket::SOL_TCP, TCP_CORK).unpack("i")[0]
- else
- @rd = @srv.kgio_accept
- end
-
- rbuf = "..."
- t0 = Time.now
- @rd.kgio_write "HI\n"
- @wr.kgio_read(3, rbuf)
- diff = Time.now - t0
- assert(diff >= 0.190, "nopush broken? diff=#{diff} > 200ms")
- assert_equal "HI\n", rbuf
- end
-
- def test_autopush_true
+ def test_compatibility
Kgio.autopush = true
assert_equal true, Kgio.autopush?
- @wr = Kgio::TCPSocket.new(@host, @port)
-
- if defined?(Strace)
- io, err = Strace.me { @rd = @srv.kgio_accept }
- assert_nil err
- lines = io.readlines
- assert_equal 1, lines.grep(/TCP_CORK/).size, lines.inspect
- assert_equal 1, @rd.getsockopt(Socket::SOL_TCP, TCP_CORK).unpack("i")[0]
- else
- @rd = @srv.kgio_accept
- end
-
- @wr.write "HI\n"
- rbuf = ""
- if defined?(Strace)
- io, err = Strace.me { @rd.kgio_read(3, rbuf) }
- assert_nil err
- lines = io.readlines
- assert lines.grep(/TCP_CORK/).empty?, lines.inspect
- assert_equal "HI\n", rbuf
- else
- assert_equal "HI\n", @rd.kgio_read(3, rbuf)
- end
-
- t0 = Time.now
- @rd.kgio_write "HI2U2\n"
- @rd.kgio_write "HOW\n"
- rc = false
-
- if defined?(Strace)
- io, err = Strace.me { rc = @rd.kgio_tryread(666) }
- else
- rc = @rd.kgio_tryread(666)
- end
-
- @wr.readpartial(666, rbuf)
- rbuf == "HI2U2\nHOW\n" or warn "rbuf=#{rbuf.inspect} looking bad?"
- diff = Time.now - t0
- assert(diff < 0.200, "time diff=#{diff} >= 200ms")
- assert_equal :wait_readable, rc
- if defined?(Strace)
- assert_nil err
- lines = io.readlines
- assert_equal 2, lines.grep(/TCP_CORK/).size, lines.inspect
- end
- @wr.close
- @rd.close
-
- @wr = Kgio::TCPSocket.new(@host, @port)
- if defined?(Strace)
- io, err = Strace.me { @rd = @srv.kgio_accept }
- assert_nil err
- lines = io.readlines
- assert lines.grep(/TCP_CORK/).empty?,"optimization fail: #{lines.inspect}"
- assert_equal 1, @rd.getsockopt(Socket::SOL_TCP, TCP_CORK).unpack("i")[0]
- end
- end
-
- def teardown
Kgio.autopush = false
+ assert_equal false, Kgio.autopush?
end
-end if RUBY_PLATFORM =~ /linux|freebsd/
+end
--
EW
next reply other threads:[~2015-08-13 20:55 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-13 20:55 Eric Wong [this message]
2016-12-15 22:50 ` [PATCH] remove autopush support and make it a no-op Eric Wong
2016-12-16 0:01 ` [PUSHED] reinstate the original (and dangerous) autopush in C Eric Wong
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