mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-01-17 04:22:27 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

A fix for Bug#5787 "mysql_stmt_prepare is upto 8 times slower":

Browse source 
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.
This commit is contained in:
konstantin@mysql.com 2005-01-25 02:31:51 +03:00
parent c33f1b6e63
commit 4a7fd21f12
1 changed files with 20 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

34
vio/viosocket.c
View file

@ -142,23 +142,29 @@ int vio_fastsend(Vio * vio __attribute__((unused)))
int r=0;
DBUG_ENTER("vio_fastsend");
#ifdef IPTOS_THROUGHPUT
#if defined(IPTOS_THROUGHPUT) && !defined(__EMX__)
{
#ifndef __EMX__
int tos = IPTOS_THROUGHPUT;
if (!setsockopt(vio->sd, IPPROTO_IP, IP_TOS, (void *) &tos, sizeof(tos)))
#endif /* !__EMX__ */
{
int nodelay = 1;
if (setsockopt(vio->sd, IPPROTO_TCP, TCP_NODELAY, (void *) &nodelay,
sizeof(nodelay))) {
DBUG_PRINT("warning",
("Couldn't set socket option for fast send"));
r= -1;
}
}
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;
}
#endif /* IPTOS_THROUGHPUT */
DBUG_PRINT("exit", ("%d", r));
DBUG_RETURN(r);
}