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Using modern sysbench to compare MyRocks and InnoDB on a small server

I used sysbench to compare MyRocks and InnoDB on a small server. I ran tests for an IO-bound and in-memory configuration and share results for the IO-bound setup here.

tl;dr

  • On some workloads InnoDB is faster than MyRocks but this does not reproduce on the faster/newer CPUs that I use at work. I wasn't able to explain this but it looks like the memory-latency bound functions in RocksDB account for more of the CPU overhead on my home servers. Maybe I need to try Intel vTune, I just wish it didn't cost $899.
  • Performance with the default my.cnf is very good for all of the engines. The optimized my.cnf is more useful on the larger servers I use at work. One change in the optimized my.cnf increases the RocksDB page size from 4kb to 16kb …
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When order of appearance of indexes matters in MySQL

Sometimes MySQL surprises you in ways you would have never imagined.

Would you think that the order in which the indexes appear in a table matters?
It does. Mind you, not the order of the columns - the order of the indexes.
MySQL optimizer can, in specific circumstances, take different paths, sometimes with nefarious effects.


Please consider the following table:

CREATE TABLE `mypartitionedtable ` (
  `HASH_ID` char(64) NOT NULL,
  `RAW_DATA` mediumblob NOT NULL,
  `EXPIRE_DATE` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
  KEY `EXPIRE_DATE_IX` (`EXPIRE_DATE`),
  KEY `HASH_ID_IX` (`HASH_ID`)
) ENGINE=TokuDB DEFAULT CHARSET=latin1 ROW_FORMAT=TOKUDB_UNCOMPRESSED
/*!50100 PARTITION BY RANGE (UNIX_TIMESTAMP(EXPIRE_DATE))
(PARTITION p2005 VALUES LESS THAN (1487847600) ENGINE = …

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How MariaDB ColumnStore Handles Big Data Workloads – Data Loading and Manipulation

How MariaDB ColumnStore Handles Big Data Workloads – Data Loading and Manipulation david_thompson_g Wed, 02/22/2017 - 18:34

MariaDB ColumnStore is a massively parallel scale out columnar database. Data loading and modification behaves somewhat differently from how a row based engine works. This article outlines the options available and how these affect performance.

Data Loading and Manipulation Options

MariaDB ColumnStore provides several options for writing data:

  1. DML operations: insert, update, delete
  2. Bulk DML: INSERT INTO … SELECT
  3. MariaDB Server bulk file load: LOAD DATA INFILE
  4. ColumnStore bulk data load: cpimport
  5. ColumnStore bulk delete: ColumnStore partition drop.

 

DML Operations

ColumnStore supports transactionally consistent insert, update, and delete statements using standard syntax. Performance of …

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MySQL Group Replication: about ack from majority

The documentation states that “For a transaction to commit, the majority of the group have to agree on the order of a given transaction in the global sequence of transactions.

This means that as soon as the majority of nodes member of the group ack the writeset reception, certification can start. So, as a picture is worth a 1000 words, this is what it looks like if we take the illustrations from my previous post:

a group of 3 members

zoom in transaction deliverthe writer also acksmajority is reached, the system agreed on the orderack of the remaining node will come too but the order has been already decided

 

certification can startthe process then continues as usual

So theoretically, having 2 nodes in one DC and 1 node in another DC shouldn’t be affected …

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Converting comma separated fields to MySQL JSON – a case study

This post is a case study of a job I had to do in a legacy application, it doesn’t mean it will apply to you, but it might.

This is a table of contents:

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Webinar Thursday, February 23, 2017: Troubleshooting MySQL Access Privileges Issues

Please join Sveta Smirnova, Percona’s Principal Technical Services Engineer, as she presents Troubleshooting MySQL Access Privileges Issues on
February 23, 2017 at 11:00 am PST / 2:00 pm EST (UTC-8).

Do you have registered users who can’t connect to the MySQL server? Strangers modifying data to which they shouldn’t have access?

MySQL supports a rich set of user privilege options and allows you to fine tune access to every object in the server. The latest versions support authentication plugins that help to create more access patterns.

However, finding errors in …

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Percona XtraBackup 2.4.6 is Now Available

Percona announces the GA release of Percona XtraBackup 2.4.6 on February 22, 2017. You can download it from our download site and apt and yum repositories.

Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as an open source solution, Percona …

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Percona XtraBackup 2.3.7 is Now Available

Percona announces the release of Percona XtraBackup 2.3.7 on February 22, 2017. Downloads are available from our download site or Percona Software Repositories.

Percona XtraBackup enables MySQL backups without blocking user queries, making it ideal for companies with large data sets and mission-critical applications that cannot tolerate long periods of downtime. Offered free as an open source solution, Percona XtraBackup drives down backup costs while providing unique features for MySQL backups.

This release is the …

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The Perfect Server CentOS 7.3 with Apache, Postfix, Dovecot, Pure-FTPD, BIND and ISPConfig 3.1

This tutorial shows how to install ISPConfig 3.1 on a CentOS 7.3 (64Bit) server. ISPConfig 3 is a web hosting control panel that allows you to configure the following services through a web browser: Apache web server, Postfix mail server, MySQL, BIND nameserver, PureFTPd, SpamAssassin, ClamAV, Mailman, and many more.

MySQL Connector/NET 6.10.1 beta has been released

MySQL Connector/Net 6.10.1 beta is the second release which supports Scaffold-DbContext, that enables the creation of corresponding model classes from an existing database that are compatible with Entity Framework (EF) Core 1.1.

To download MySQL Connector/Net 6.10.1 beta, see the “Development Releases” tab at http://dev.mysql.com/downloads/connector/net/

Changes in MySQL Connector/Net 6.10.1 (2017-02-22, Beta)

Known limitations of this release:

* The output classes cannot exist prior to using the EF Core database first feature.

* The target database must have a table with a primary key.

* The target database cannot contain one or more views.

* The JSON data exchange format is not supported by the EF Core database first feature.

* No error message is provided when a table given as input does not …

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