mariadb/vio/viosocket.c
unknown dc43c6ea4b A fix for Bug#5787 "mysql_stmt_prepare is upto 8 times slower":
it's crucial to disable Nagle algorithm on client for no-reply commands
(like mysql_stmt_free) to always work fast.
Nagle algorithm instructs the sender to buffer (store) data if any 
unacknowledged data is outstanding and the size of to-send data is less than
the network segment. It was exactly the case with COM_STMT_CLOSE after 
COM_STMT_PREPARE, so the client was waiting for Nagle timer to expire or
 for ACK from the server, while the server was holding up ACK because of 
delayed acknowledgement algorithm.
The tricky part is that we have been already disabling Nagle 
algorithm (by setting TCP_NODELAY)
almost everywhere except Windows (and maybe Netware).
It is the reason why the bug was repeatable only with Windows client.


vio/viosocket.c:
  A fix for Bug#5787 "mysql_stmt_prepare is upto 8 times slower":
  if we disable Nagle algorithm, do it everywhere.
2005-01-25 02:31:51 +03:00

500 lines
12 KiB
C

/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Note that we can't have assertion on file descriptors; The reason for
this is that during mysql shutdown, another thread can close a file
we are working on. In this case we should just return read errors from
the file descriptior.
*/
#include "vio_priv.h"
int vio_errno(Vio *vio __attribute__((unused)))
{
return socket_errno; /* On Win32 this mapped to WSAGetLastError() */
}
int vio_read(Vio * vio, gptr buf, int size)
{
int r;
DBUG_ENTER("vio_read");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
#ifdef __WIN__
r = recv(vio->sd, buf, size,0);
#else
errno=0; /* For linux */
r = read(vio->sd, buf, size);
#endif /* __WIN__ */
#ifndef DBUG_OFF
if (r < 0)
{
DBUG_PRINT("vio_error", ("Got error %d during read",errno));
}
#endif /* DBUG_OFF */
DBUG_PRINT("exit", ("%d", r));
DBUG_RETURN(r);
}
int vio_write(Vio * vio, const gptr buf, int size)
{
int r;
DBUG_ENTER("vio_write");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
#ifdef __WIN__
r = send(vio->sd, buf, size,0);
#else
r = write(vio->sd, buf, size);
#endif /* __WIN__ */
#ifndef DBUG_OFF
if (r < 0)
{
DBUG_PRINT("vio_error", ("Got error on write: %d",socket_errno));
}
#endif /* DBUG_OFF */
DBUG_PRINT("exit", ("%d", r));
DBUG_RETURN(r);
}
int vio_blocking(Vio * vio __attribute__((unused)), my_bool set_blocking_mode,
my_bool *old_mode)
{
int r=0;
DBUG_ENTER("vio_blocking");
*old_mode= test(!(vio->fcntl_mode & O_NONBLOCK));
DBUG_PRINT("enter", ("set_blocking_mode: %d old_mode: %d",
(int) set_blocking_mode, (int) *old_mode));
#if !defined(___WIN__) && !defined(__EMX__)
#if !defined(NO_FCNTL_NONBLOCK)
if (vio->sd >= 0)
{
int old_fcntl=vio->fcntl_mode;
if (set_blocking_mode)
vio->fcntl_mode &= ~O_NONBLOCK; /* clear bit */
else
vio->fcntl_mode |= O_NONBLOCK; /* set bit */
if (old_fcntl != vio->fcntl_mode)
r = fcntl(vio->sd, F_SETFL, vio->fcntl_mode);
}
#else
r= set_blocking_mode ? 0 : 1;
#endif /* !defined(NO_FCNTL_NONBLOCK) */
#else /* !defined(__WIN__) && !defined(__EMX__) */
#ifndef __EMX__
if (vio->type != VIO_TYPE_NAMEDPIPE)
#endif
{
ulong arg;
int old_fcntl=vio->fcntl_mode;
if (set_blocking_mode)
{
arg = 0;
vio->fcntl_mode &= ~O_NONBLOCK; /* clear bit */
}
else
{
arg = 1;
vio->fcntl_mode |= O_NONBLOCK; /* set bit */
}
if (old_fcntl != vio->fcntl_mode)
r = ioctlsocket(vio->sd,FIONBIO,(void*) &arg, sizeof(arg));
}
#ifndef __EMX__
else
r= test(!(vio->fcntl_mode & O_NONBLOCK)) != set_blocking_mode;
#endif /* __EMX__ */
#endif /* !defined(__WIN__) && !defined(__EMX__) */
DBUG_PRINT("exit", ("%d", r));
DBUG_RETURN(r);
}
my_bool
vio_is_blocking(Vio * vio)
{
my_bool r;
DBUG_ENTER("vio_is_blocking");
r = !(vio->fcntl_mode & O_NONBLOCK);
DBUG_PRINT("exit", ("%d", (int) r));
DBUG_RETURN(r);
}
int vio_fastsend(Vio * vio __attribute__((unused)))
{
int r=0;
DBUG_ENTER("vio_fastsend");
#if defined(IPTOS_THROUGHPUT) && !defined(__EMX__)
{
int tos = IPTOS_THROUGHPUT;
r= setsockopt(vio->sd, IPPROTO_IP, IP_TOS, (void *) &tos, sizeof(tos));
}
#endif /* IPTOS_THROUGHPUT && !__EMX__ */
if (!r)
{
#ifdef __WIN__
BOOL nodelay= 1;
r= setsockopt(vio->sd, IPPROTO_TCP, TCP_NODELAY, (const char*) &nodelay,
sizeof(nodelay));
#else
int nodelay = 1;
r= setsockopt(vio->sd, IPPROTO_TCP, TCP_NODELAY, (void*) &nodelay,
sizeof(nodelay));
#endif /* __WIN__ */
}
if (r)
{
DBUG_PRINT("warning", ("Couldn't set socket option for fast send"));
r= -1;
}
DBUG_PRINT("exit", ("%d", r));
DBUG_RETURN(r);
}
int vio_keepalive(Vio* vio, my_bool set_keep_alive)
{
int r=0;
uint opt = 0;
DBUG_ENTER("vio_keepalive");
DBUG_PRINT("enter", ("sd=%d, set_keep_alive=%d", vio->sd, (int)
set_keep_alive));
if (vio->type != VIO_TYPE_NAMEDPIPE)
{
if (set_keep_alive)
opt = 1;
r = setsockopt(vio->sd, SOL_SOCKET, SO_KEEPALIVE, (char *) &opt,
sizeof(opt));
}
DBUG_RETURN(r);
}
my_bool
vio_should_retry(Vio * vio __attribute__((unused)))
{
int en = socket_errno;
return (en == SOCKET_EAGAIN || en == SOCKET_EINTR ||
en == SOCKET_EWOULDBLOCK);
}
int vio_close(Vio * vio)
{
int r=0;
DBUG_ENTER("vio_close");
#ifdef __WIN__
if (vio->type == VIO_TYPE_NAMEDPIPE)
{
#if defined(__NT__) && defined(MYSQL_SERVER)
CancelIo(vio->hPipe);
DisconnectNamedPipe(vio->hPipe);
#endif
r=CloseHandle(vio->hPipe);
}
else
#endif /* __WIN__ */
if (vio->type != VIO_CLOSED)
{
DBUG_ASSERT(vio->sd >= 0);
if (shutdown(vio->sd,2))
r= -1;
if (closesocket(vio->sd))
r= -1;
}
if (r)
{
DBUG_PRINT("vio_error", ("close() failed, error: %d",socket_errno));
/* FIXME: error handling (not critical for MySQL) */
}
vio->type= VIO_CLOSED;
vio->sd= -1;
DBUG_RETURN(r);
}
const char *vio_description(Vio * vio)
{
return vio->desc;
}
enum enum_vio_type vio_type(Vio* vio)
{
return vio->type;
}
my_socket vio_fd(Vio* vio)
{
return vio->sd;
}
my_bool vio_peer_addr(Vio * vio, char *buf, uint16 *port)
{
DBUG_ENTER("vio_peer_addr");
DBUG_PRINT("enter", ("sd: %d", vio->sd));
if (vio->localhost)
{
strmov(buf,"127.0.0.1");
*port= 0;
}
else
{
size_socket addrLen = sizeof(vio->remote);
if (getpeername(vio->sd, (struct sockaddr *) (&vio->remote),
&addrLen) != 0)
{
DBUG_PRINT("exit", ("getpeername gave error: %d", socket_errno));
DBUG_RETURN(1);
}
my_inet_ntoa(vio->remote.sin_addr,buf);
*port= ntohs(vio->remote.sin_port);
}
DBUG_PRINT("exit", ("addr: %s", buf));
DBUG_RETURN(0);
}
void vio_in_addr(Vio *vio, struct in_addr *in)
{
DBUG_ENTER("vio_in_addr");
if (vio->localhost)
bzero((char*) in, sizeof(*in)); /* This should never be executed */
else
*in=vio->remote.sin_addr;
DBUG_VOID_RETURN;
}
/* Return 0 if there is data to be read */
my_bool vio_poll_read(Vio *vio,uint timeout)
{
#ifndef HAVE_POLL
return 0;
#else
struct pollfd fds;
int res;
DBUG_ENTER("vio_poll");
fds.fd=vio->sd;
fds.events=POLLIN;
fds.revents=0;
if ((res=poll(&fds,1,(int) timeout*1000)) <= 0)
{
DBUG_RETURN(res < 0 ? 0 : 1); /* Don't return 1 on errors */
}
DBUG_RETURN(fds.revents & POLLIN ? 0 : 1);
#endif
}
void vio_timeout(Vio *vio __attribute__((unused)),
uint timeout __attribute__((unused)))
{
#ifdef __WIN__
ulong wait_timeout= (ulong) timeout * 1000;
(void) setsockopt(vio->sd, SOL_SOCKET, SO_RCVTIMEO, (char*) &wait_timeout,
sizeof(wait_timeout));
#endif /* __WIN__ */
}
#ifdef __WIN__
int vio_read_pipe(Vio * vio, gptr buf, int size)
{
DWORD length;
DBUG_ENTER("vio_read_pipe");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
if (!ReadFile(vio->hPipe, buf, size, &length, NULL))
DBUG_RETURN(-1);
DBUG_PRINT("exit", ("%d", length));
DBUG_RETURN(length);
}
int vio_write_pipe(Vio * vio, const gptr buf, int size)
{
DWORD length;
DBUG_ENTER("vio_write_pipe");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
if (!WriteFile(vio->hPipe, (char*) buf, size, &length, NULL))
DBUG_RETURN(-1);
DBUG_PRINT("exit", ("%d", length));
DBUG_RETURN(length);
}
int vio_close_pipe(Vio * vio)
{
int r;
DBUG_ENTER("vio_close_pipe");
#if defined(__NT__) && defined(MYSQL_SERVER)
CancelIo(vio->hPipe);
DisconnectNamedPipe(vio->hPipe);
#endif
r=CloseHandle(vio->hPipe);
if (r)
{
DBUG_PRINT("vio_error", ("close() failed, error: %d",GetLastError()));
/* FIXME: error handling (not critical for MySQL) */
}
vio->type= VIO_CLOSED;
vio->sd= -1;
DBUG_RETURN(r);
}
void vio_ignore_timeout(Vio *vio __attribute__((unused)),
uint timeout __attribute__((unused)))
{
}
#ifdef HAVE_SMEM
int vio_read_shared_memory(Vio * vio, gptr buf, int size)
{
int length;
int remain_local;
char *current_postion;
DBUG_ENTER("vio_read_shared_memory");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
remain_local = size;
current_postion=buf;
do
{
if (vio->shared_memory_remain == 0)
{
HANDLE events[2];
events[0]= vio->event_server_wrote;
events[1]= vio->event_conn_closed;
/*
WaitForMultipleObjects can return next values:
WAIT_OBJECT_0+0 - event from vio->event_server_wrote
WAIT_OBJECT_0+1 - event from vio->event_conn_closed. We can't read anything
WAIT_ABANDONED_0 and WAIT_TIMEOUT - fail. We can't read anything
*/
if (WaitForMultipleObjects(2, (HANDLE*)&events,FALSE,
vio->net->read_timeout*1000) != WAIT_OBJECT_0)
{
DBUG_RETURN(-1);
};
vio->shared_memory_pos = vio->handle_map;
vio->shared_memory_remain = uint4korr((ulong*)vio->shared_memory_pos);
vio->shared_memory_pos+=4;
}
length = size;
if (vio->shared_memory_remain < length)
length = vio->shared_memory_remain;
if (length > remain_local)
length = remain_local;
memcpy(current_postion,vio->shared_memory_pos,length);
vio->shared_memory_remain-=length;
vio->shared_memory_pos+=length;
current_postion+=length;
remain_local-=length;
if (!vio->shared_memory_remain)
if (!SetEvent(vio->event_client_read)) DBUG_RETURN(-1);
} while (remain_local);
length = size;
DBUG_PRINT("exit", ("%d", length));
DBUG_RETURN(length);
}
int vio_write_shared_memory(Vio * vio, const gptr buf, int size)
{
int length;
uint remain;
HANDLE pos;
int sz;
char *current_postion;
DBUG_ENTER("vio_write_shared_memory");
DBUG_PRINT("enter", ("sd=%d, buf=%p, size=%d", vio->sd, buf, size));
remain = size;
current_postion = buf;
while (remain != 0)
{
if (WaitForSingleObject(vio->event_server_read, vio->net->write_timeout*1000)
!= WAIT_OBJECT_0)
{
DBUG_RETURN(-1);
};
sz = remain > shared_memory_buffer_length ? shared_memory_buffer_length: remain;
int4store(vio->handle_map,sz);
pos = vio->handle_map + 4;
memcpy(pos,current_postion,sz);
remain-=sz;
current_postion+=sz;
if (!SetEvent(vio->event_client_wrote)) DBUG_RETURN(-1);
}
length = size;
DBUG_PRINT("exit", ("%d", length));
DBUG_RETURN(length);
}
int vio_close_shared_memory(Vio * vio)
{
int r;
DBUG_ENTER("vio_close_shared_memory");
if (vio->type != VIO_CLOSED)
{
/*
Set event_conn_closed for notification of both client and server that
connection is closed
*/
SetEvent(vio->event_conn_closed);
/*
Close all handlers. UnmapViewOfFile and CloseHandle return non-zero
result if they are success.
*/
r= UnmapViewOfFile(vio->handle_map) || CloseHandle(vio->event_server_wrote) ||
CloseHandle(vio->event_server_read) || CloseHandle(vio->event_client_wrote) ||
CloseHandle(vio->event_client_read) || CloseHandle(vio->handle_file_map);
if (!r)
{
DBUG_PRINT("vio_error", ("close() failed, error: %d",r));
/* FIXME: error handling (not critical for MySQL) */
}
}
vio->type= VIO_CLOSED;
vio->sd= -1;
DBUG_RETURN(!r);
}
#endif /* HAVE_SMEM */
#endif /* __WIN__ */