What could cause a MySQL database to be extremely slow?

What could cause a MySQL database to be extremely slow?

I’m trying to figure out why a MySQL database is abnormally slow on a live server. Deleting a row from a table (with only less than 100 rows) can take anywhere between 1 second and 20 seconds. I’ve checked the running processes and cannot see anything that would take out all the CPU or memory.

What’s the best way to optimize MySQL server?

Make sure you restart the mysql server after every configuration change: Next up, let’s focus on Indexes – the main pain point of many hobbyist DB admins! Especially those who immediately jump into ORMs and are thus never truly exposed to raw SQL. Note: the terms keys and indexes can be used interchangeably.

How can I reduce MySQL usage on my website?

As site traffic grows, these limits prove inadequate for its proper functioning. We rescue websites from this situation by using PHP OpCode cache, which reduces queries to the database, and thereby reduce MySQL induced I/O and CPU usage. In many sites, caching resolved the resource bottlenecks.

What to do if your MySQL server is not running?

When we find an unoptimized MySQL server, we run an audit and fix incorrect settings. Some common ones we tweak are: innodb_buffer_pool_size – The size of buffer (cache of old queries) in InnoDB databases. Usually set to 50-70% of available memory. key_buffer_size – The buffer size for MyISAM databases. Usually set to 20% of available memory.

Why is my connection to localhost so slow?

For me it was this solution I found here, If IP6 connectivity is enabled, connection to “localhost” may be slow, instead use the ip address, 127.0.0.1. This worked for me. firewalls, Internet, routing etc etc slows down your connection. You should put your database on a intra net instead. Keep it local and behind your big firewall.

Why does JDBC take so long to connect to MySQL?

I use JDBC to connect to MySQL. When it’s at localhost:3306, everything is OK. But when I move my application to another computer in the intranet, and use :3306 to connect to the MySQL database, it takes about 1 minute to connect to MySQL successfully. What’s up with this? Well it could be a DNS problem.

Why is my Linux server running so slow?

This is the case in the video below, load averages are above 30 on a server with 24 cores, but CPU shows around 70 percent idle. One of the common causes of this condition is disk I/O bottleneck. What is I/O wait bottleneck?

How can I tell if disk I / O is slowing down my server?

I/O Wait is the percentage of time the CPU had to wait on storage. Let’s look at how we can confirm if disk I/O is slowing down application performance by using a few terminal command-line tools ( top, atop and iotop) on a lemp-installed web server.

Why does the Linux kernel Oom kill MySQL?

Growing to the point where the Linux Kernel would OOM kill MySQL. Considering MySQL’s max allocated memory equals the size of per-thread buffers multiplied by that ‘max_connections=2000’ setting, this also left PHP-FPM with little free memory as it also piled up connections waiting on MySQL < disk.

Are there any performance issues with MySQL database?

Performance issues are common problems when administering MySQL databases. Sometimes these problems are, in fact, due to slow queries. In this blog, we’ll deal with slow queries and how to identify these. MySQL has the capability to filter and log slow queries.

What causes MySQL to have poor response time?

But in its default settings, MySQL tries to use all of server’s memory, causing swap to be used; And swap usage leads to poor speed and response times. When we find an unoptimized MySQL server, we run an audit and fix incorrect settings. Some common ones we tweak are:

Why is MySQL running on a low memory?

MySQL is then forced to run on a very low available memory and I/O, causing it to use the disk-based Swap memory, thereby slowing down the server. Ideally MySQL should run in its own independent server. However, this is not economical. So, you might run related services together – such as Web, DNS and MySQL.