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Questions tagged [max-connections]

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Maximum concurrent connections to SQL Server Express 2017 installed on Windows Server 2016 Essentials

If I install SQL Server Express 2017 on Windows Server 2016 Essentials, what is the maximum number of users that will be able to connect concurrently across the network to the SQL Server Express ...
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1answer
38 views

max_connections error during restoring PostgreSQL to Local Database

I am facing max_connections error during database restoration on ApsaraDB for PostgreSQL in a local database. I am using below mentioned command for database restoration \i c:/mydb1.sql
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0answers
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Oracle Max Open Cursors - What does table_ mean?

We're encountering a lot of maximum open cursors recently so we ran a query to check for the maximum open cursors. The query to check for open cursors looks something like this select * from v$...
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2answers
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WARN max_connections from pt-variable-advisor - what to configure for DBaaS?

Our VM configuration (hosted on Vmware) # cat /proc/cpuinfo |grep "cpu cores" | awk -F: '{ num+=$2 } END{ print "cpu cores", num }' cpu cores 32 # free -h total used free ...
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1answer
764 views

What reason could cause AWS RDS connections to

It's my first time using RDS on AWS, I use a t2.medium instance running MySQL Aurora with default configs. The CPU usage and DB connections is quite normal until "something" happen, which cause the DB ...
4
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1answer
740 views

Is it normal to constantly have 30+ connections to ‘master’ database in MS SQL Server 2012?

In troubleshooting why I was seeing so many connections to one of our internally used databases in SQL Server 2012. A query I found online that had been helpful to me was this: SELECT DB_NAME(sP....
4
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1answer
125 views

Confused about maximum connections in PostgreSQL

I am building a web application and I using PostgreSQL as the database management system. The following page details the maximum connections setting: https://www.postgresql.org/docs/9.5/static/...
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1answer
521 views

How can I find the source of postgresql per-connection memory leaks?

I'm using postgresql 9.5.4 on amazon RDS with ~1300 persistent connections from rails 4.2 with "prepared_statements: false". Over the course of hours and days, the "Freeable Memory" RDS stat ...
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1answer
82 views

systems hangs after specific time

I am having 2 applications (Java and PHP). Both are sharing same DB Server. After specific time, both systems stops working due to "Too many connections". I tried so many settings (increased ...
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1answer
370 views

Pooler (pgbouncer) + MasterDB + Slaves

During a spike, my connections go from 30 to over 140, as you can see below: I'm willing to set-up a pooler like pgbouncer, but have some questions as my scenario is not that easy: 1 Load Balancer ...
0
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1answer
604 views

max_allowed_packet after mysql restart

I want to set max_allowed_packet parameter in runtime. The SET GLOBAL max_allowed_packet = 16777216 works for new connections, but after database server restart, it has previous value. Can value of ...
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0answers
90 views

Exactly what are MySQL connections? [closed]

There are tons of questions on how to deal with errors around reaching the maximum number of connections in MySQL. I often program in PHP so answers generally range from changing the max_connections ...
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2answers
898 views

ulimit 'open files' and MySQL max_connection

When running mysql on SSD, does max_connections, if set more than the kernel's ulimit open files, be limited to the kernel's limit? My understanding is that if the kernel's ulimit open files is 1024 ...
6
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1answer
11k views

How many users are supported on SQL Server 2012 Express?

I would like to say that i have gone through some of the sql blog and MSDN BOL, but still there is some confusion in mind like. The limitation of SQL Server 2012 Express is 10 GB. It is the ...
2
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0answers
39 views

Database connections and related issues?

If my tomcat is configured to accept 100 incoming requests concurrently, how many connections should be present in DB connection pool ? In other words, if there a known optimal ratio of number of ...
2
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1answer
665 views

MySQL max_connections setting - per client or global?

So I just need to clear this up. For a test, I set max_connections=10 in my.cnf. I then ran 10 scripts concurrently that each take over 20 seconds to finish. I monitored my threads and noticed that ...
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0answers
378 views

How to get past Windows Server rate limiting repeated SQL Server connections over network? [closed]

Currently I have ETL software installed/ running on a machine separate from the destination data warehouse database (for security purposes apparently). So it must send data/ write records across a ...
7
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2answers
14k views

View active MySQL connections per user

I need a query that will give me the active or open number of connections to a certain database for a certain user. I have been searching for hours and have come up with nothing so far. I am close, so ...
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3answers
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Alternating usernames while connecting to mysql database

My server has a max_connections value of 400 and a max_user_connections of 250. Since I am always connecting with the same user name, my effective max_connections is 250 instead of 400. To solve this, ...
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1answer
60 views

MySQL max_connctions+1

I experienced an incident that my connections are full. Even I as an administrator I cannot log to MySQL due to "too many connections.". Does anybody knows how to setup this max_connections+1? I use ...
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1answer
23k views

What limits the number of connections?

As per https://devcenter.heroku.com/articles/heroku-postgres-legacy-plans the connection limit is 500 As per https://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server "Generally, PostgreSQL on ...
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3answers
2k views

How to understand the PostgreSQL discrepancy between connection pool recommendation ((2 * n_cores) + n_disks) and support for 100s of connections?

From PostgreSQL docs: Number of Database Connections -> How to Find the Optimal Database Connection Pool Size for optimal throughput the number of active connections should be somewhere near ((...
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1answer
536 views

too many connection error mysql: how to calculate max_connections

how to calculate this values to get the best results to resolve this error "too many connection error mysql" and make my API faster in mysql wait_timeout = ?? max_connections = ?? ...
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3answers
299 views

What is the meaning of “available RAM” for calculating MySQL max_connections

The question was asked previously, "how do I calculate MySQL max_connections" and this was the answer: max_connections = (Available RAM - Global Buffers) / Thread Buffers Since I don't have enough ...
2
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1answer
7k views

pt-heartbeat showing “Host is blocked because of many connection errors”…but connections are well under limit

I'm running MySQL in a master-slave configuration. pt-heartbeat is showing "Host is blocked because of many connection errors"...but connections are well under limit (limit is 600 connections, MySQL ...
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2answers
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psql: FATAL: sorry, too many clients already

I am suddenly getting this error when either trying to access the website that uses the postgresql database, or even when using the psql utility or pgadmin3. My database is set to handle 150 maximum ...
0
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1answer
2k views

Find the last SQL statement executed for a given connection

MySQL running on Windows 7 64 bit. I'm trying to track down a leak of connections, I'm pretty sure the only ASP.NET app using the server is at fault here. We received the "Too many connections" ...
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3answers
3k views

Can we restrict the number of connections to a database in SQL Server?

I have a database on SQL Server. My web application contacts this database. Is there a way in which I can restrict the number of connections to this database through some settings on the SQL Server?
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1answer
2k views

MySQL max_connection value

Questions I got a 12 GB machine with apache & myqsl, i have may apache max_client set to 150 will this cause some bottlenecks with the 50 max_connection in mysql? What value should I set mysql ...
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2answers
21k views

How can I determine the maximum possible number of threads?

What factors determine the maximum possible number of threads mysqld will create? I only care about consideration for mysql and not limitations that may be imposed by the operating system. Further, I ...
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2answers
2k views

multiple connections on MySQL database with no users on httpd

My database seems to have many open connections despite having no users on httpd. mysql> SHOW PROCESSLIST; +-------+----------+--------------------+---------------------+---------+------+-------+--...
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1answer
2k views

Why does max_connections in my.ini not match concurrent connections in Mysql instance config wizard?

MySQL 5.1.x | Windows Server 2003 Can someone please clarify why max_connections in my.ini is much larger than the manual value I specify in the Concurrent Connections Dialogue? For example, if I ...
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1answer
815 views

Does the mysql parameter “max_connections” apply for unix socket connections?

The documentation does not specify if max_connections apply only to TCP connections. The way it is said, it looks like it does apply for any kind of connection, but I'd like to be sure because ...
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1answer
95k views

How to get rid of “maximum user connections” error ?

I am using MySQLi for my webapp but whenever I want to visit some particular page, I get mysqli_connect() [function.mysqli-connect]: (42000/1203): User ***_user already has more than '...
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2answers
7k views

MySQL PDO Cannot assign requested address

Can someone help me with this error? [08-Apr-2013 17:44:08 Europe/Berlin] PHP Warning: PDO::__construct(): [2002] Cannot assign requested address (trying to connect via tcp://****:3306) in /...
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2answers
3k views

Does PgBouncer create a separate pool for every database config entry?

If I set up a pgbouncer.ini config file with several database entries, does pgBouncer create a separate pool for each one? I would think so, but have not been able to confirm this. For example, ...
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0answers
891 views

How to properly configure pgBouncer transaction level pooling?

What is a good way to determine the number of available transaction connections when using pgBouncer to pool database connections? Also, how should I determine the number of max_connections and ...
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1answer
4k views

mysql fine tuning: open_tables, opened_tables

I'm a novice to database administration and have been depending on forum suggestions and answers to help resolve my database hang ups and too many connections errors; I've managed to reduce the ...
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1answer
3k views

Show processlist / Max concurrent connections seem to max out at 131

When I put my database under a load test (basically just a basic write and basic read from our app), and run show processlist; in the middle of it, there is always 131 rows in the set and that's it. I'...
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1answer
5k views

Mysql not closing connections

I have a Java application that configured with a connection pool. I have ensured that the application terminates the connections properly. However when I run this command on mysql command line - ...
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0answers
45 views

Max connections sql server express could have? [duplicate]

Possible Duplicate: Max connections SQL Server Express could have? I have sql server 2005 express edition installed on one of my client's machine, and lots of other users are also connected to ...
3
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1answer
1k views

Named pipes connection closed when subjected to load

We're hosting a service where we have a messaging service. When a message arrives, it checks which subscribers it should be sent to by connecting to the database, and querying the subscriptions table....
4
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1answer
23k views

Why does max_used_connections status not get refreshed automatically once it reaches max_connections, even though the Threads_connected falls down

I always wonder, why does the max_used_connections value not come down, once it reaches the peak value of max_connections? I always flush the status and bring down this value to avoid DB connection ...
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2answers
4k views

Too many TIME_WAIT connections in PostgreSQL

I am using PostgreSQL 9.0 on Centos 5.7 Final. At any given there are around 1,500-2,200 connections open for PostgreSQL on port 5432 which are in TIME_WAIT state. I have a feeling this is not good. ...
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1answer
401 views

Sudden MySQL connection issue

We have almost 60 network guys working via a proxy server, developing on one Linux-based in-house server. Suddenly, it is saying to everyone: Warning: mysql_connect() [function.mysql-connect]: Too ...
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2answers
2k views

Are problems with parallelism more common today? What issues can arise from parallelism?

This is a very general question so I don't give much specific information. I am more interested in parallelism and its possible drawbacks. Generally I am all for parallelism as something useful and ...
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1answer
6k views

What are user connections - when are the created and destroyed?

We've been getting an intermittent error on out site: Warning: mysql_connect() [function.mysql-connect]: User '557574_prod' has exceeded the 'max_user_connections' resource (current value: 10) ...
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3answers
38k views

How do you calculate mysql max_connections variable?

How do you calculate mysql max_connections ? What do you take into consideration ?