Hi Patrick! This is the result of sockets being kept around in the kernel in the TIME_WAIT state so any axtra TCP packets can be flushed out. The 28000 is the default port range available for socket connections. You can see this with:
# cat /proc/sys/net/ipv4/tcp_fin_timeout 60 # cat /proc/sys/net/ipv4/ip_local_port_range 32768 61000 61000-32768= 28232 (these are the defaults on Debian Linux). So you only have a pool of 28232 sockets to work with, and each will linger around for 60 seconds in a TIME_WAIT state even after being close()d on both ends. You can increase your port range and lower your TIME_WAIT value, but it's only buying you a larger window. If you push connects/disconnects through fast enough you'll hit the new limit. :) Something to keep in mind though for servers that have a high connect rate. -Eric On Thu, Jul 09, 2009 at 12:26:11PM -0400, Patrick Galbraith wrote: > Hi all, > > I am in the process of trying to get sql-bench to work with Drizzle, and > stumbled into this issue that at first I thought was a problem with > DBD::drizzle, but in reducing the problem to a simple C program, the > problem still exists. All the program does is connect, select one row > from a table with a single record, disconnect, in a loop that goes as > high as 100k. It most often fails at 28,200 or so connections. The Perl > test in sql-bench is test-insert. When I ran the Perl program through > valgrind, it slowed the execution enough for the test to succeed with > 100k settings. > > If I run the test right after failing, it doesn't work, as well as > connecting using the drizzle client. > > --Patrick > -- DRIZZLE dump 10.13 Distrib 0.3, for unknown-linux-gnu (x86_64) > -- > -- Host: localhost Database: test > -- ------------------------------------------------------ > -- Server version 2009.06.1058 > SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; > SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; > > -- > -- Table structure for table `bench1` > -- > > DROP TABLE IF EXISTS `bench1`; > CREATE TABLE `bench1` ( > `a` int NOT NULL, > `i` int DEFAULT NULL, > `s` varchar(10) DEFAULT NULL, > PRIMARY KEY (`a`) > ) ENGINE=InnoDB; > > -- > -- Dumping data for table `bench1` > -- > > ALTER TABLE `bench1` DISABLE KEYS; > INSERT INTO `bench1` VALUES (1,100,'AAA'); > ALTER TABLE `bench1` ENABLE KEYS; > SET foreign_key_chec...@old_foreign_key_checks; > SET unique_chec...@old_unique_checks; > -- Dump completed on 2009-07-08 17:42:08 > /* > * Drizzle Client & Protocol Library > * > * Copyright (C) 2008 Eric Day ([email protected]) > * All rights reserved. > * > * Use and distribution licensed under the BSD license. See > * the COPYING file in this directory for full text. > */ > > #include <stdio.h> > #include <string.h> > > #include <libdrizzle/drizzle_client.h> > > int main(int argc, char *argv[]) > { > char query[100]; > drizzle_con_st con; > drizzle_result_st result; > drizzle_return_t ret; > char **row; > int i= 1; > > for (i= 1; i <= 100000; i++ ) > { > sprintf(query, "select a,i,s,%d from bench1", i); > if (drizzle_con_create(NULL, &con) == NULL) > { > printf("drizzle_con_create:NULL\n"); > return 1; > } > > drizzle_con_set_db(&con, "test"); > > (void)drizzle_query_str(&con, &result, query, &ret); > if (ret != DRIZZLE_RETURN_OK) > { > printf("query %s\n", query); > printf("drizzle_query:%s\n", drizzle_con_error(&con)); > return 1; > } > > ret= drizzle_result_buffer(&result); > if (ret != DRIZZLE_RETURN_OK) > { > printf("drizzle_result_buffer:%s\n", drizzle_con_error(&con)); > return 1; > } > > drizzle_result_free(&result); > drizzle_con_free(&con); > } > > return 0; > } > _______________________________________________ > Mailing list: https://launchpad.net/~drizzle-discuss > Post to : [email protected] > Unsubscribe : https://launchpad.net/~drizzle-discuss > More help : https://help.launchpad.net/ListHelp _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
