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Search Results for: cpu bound

Performance problem with Innodb and DROP TABLE

I’ve been working with an application which does a lot of CREATE and DROP table for Innodb tables and we’ve discovered DROP TABLE can take a lot of time and when it happens a lot …

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MySQL Partitioning – can save you or kill you

I wanted for a while to write about using MySQL Partitioning for Performance Optimization and I just got a relevant customer case to illustrate it. First you need to understand how partitions work internally. Partitions …

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Shard-Query adds parallelism to queries

Preamble: On performance, workload and scalability: MySQL has always been focused on OLTP workloads. In fact, both Percona Server and MySQL 5.5.7rc have numerous performance improvements which benefit workloads that have high concurrency. Typical OLTP …

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Impact of the sort buffer size in MySQL

The parameter sort_buffer_size is one the MySQL parameters that is far from obvious to adjust. It is a per session buffer that is allocated every time it is needed. The problem with the sort buffer …

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Scaling: Consider both Size and Load

So lets imagine you have the server handling 100.000 user accounts. You can see the CPU,IO and Network usage is below 10% of capacity – does it mean you can count on server being able …

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Star Schema Bechmark: InfoBright, InfiniDB and LucidDB

In my previous rounds with DataWarehouse oriented engines I used single table without joins, and with small (as for DW) datasize (see https://www.percona.com/blog/2009/10/02/analyzing-air-traffic-performance-with-infobright-and-monetdb/, https://www.percona.com/blog/2009/10/26/air-traffic-queries-in-luciddb/, https://www.percona.com/blog/2009/11/02/air-traffic-queries-in-infinidb-early-alpha/). Addressing these issues, I took Star Schema Benchmark, which is …

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How many partitions can you have ?

I had an interesting case recently. The customer dealing with large MySQL data warehouse had the table which was had data merged into it with INSERT ON DUPLICATE KEY UPDATE statements. The performance was extremely …

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table_cache negative scalability

Couple of months ago there was a post by FreshBooks on getting great performance improvements by lowering table_cache variable. So I decided to investigate what is really happening here. The “common sense” approach to tuning …

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MySQL-Memcached or NOSQL Tokyo Tyrant – part 2

Part 1 of our series set-up our “test”  application and looked at boosting performance of the application by buffer MySQL with memcached.  Our test application is simple and requires only 3 basic operations per transaction …

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Just do the math!

One of the most typical reasons for performance and scalability problems I encounter is simply failing to do the math. And these are typically bad one because it often leads to implementing architectures which are …

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