MySQL Performance Tuning. Part 1: MySQL Configuration (includes MySQL 5.7)Aurimas Mikalauskas
Is my MySQL server configured properly? Should I run Community MySQL, MariaDB, Percona or WebScaleSQL? How many innodb buffer pool instances should I run? Why should I NOT use the query cache? How do I size the innodb log file size and what IS that innodb log anyway? All answers are inside.
Aurimas Mikalauskas is a former Percona performance consultant and architect currently writing and teaching at speedemy.com. He's been involved with MySQL since 1999, scaling and optimizing MySQL backed systems since 2004 for companies such as BBC, EngineYard, famous social networks and small shops like EstanteVirtual, Pine Cove and hundreds of others.
Additional content mentioned in the presentation can be found here: http://speedemy.com/17
MySQL Performance Tuning. Part 1: MySQL Configuration (includes MySQL 5.7)Aurimas Mikalauskas
Is my MySQL server configured properly? Should I run Community MySQL, MariaDB, Percona or WebScaleSQL? How many innodb buffer pool instances should I run? Why should I NOT use the query cache? How do I size the innodb log file size and what IS that innodb log anyway? All answers are inside.
Aurimas Mikalauskas is a former Percona performance consultant and architect currently writing and teaching at speedemy.com. He's been involved with MySQL since 1999, scaling and optimizing MySQL backed systems since 2004 for companies such as BBC, EngineYard, famous social networks and small shops like EstanteVirtual, Pine Cove and hundreds of others.
Additional content mentioned in the presentation can be found here: http://speedemy.com/17
High performance and high availability proxies for MySQLMydbops
This is presented at LSPE meet up on 17-06-2017.
ProxySQL and MaxScale are the next-generation database proxy that manages security, scalability, high availability and data streaming in scale-out deployments
ProxySQL and MaxScale have been most widely adapted in industry these days. They can be used in smaller platforms to bigger platforms. The Objective of this talk is to make awareness about the next-gen database proxies and their value addition.
Tuning the Memory and Optimizer Parameters - This topic has come quite often in requests and suggestions from our regular viewers and followers of our Postgres Hangouts.
So we picked it up as the topic for this month's Postgres Hangout. This time we will try to explore and share on Memory and Memory .
Join us as we discuss what impacts your decision before you put a number against each of these important parameters!
Technical Introduction to PostgreSQL and PPASAshnikbiz
Let's take a look at:
PostgreSQL and buzz it has created
Architecture
Oracle Compatibility
Performance Feature
Security Features
High Availability Features
DBA Tools
User Stories
What’s coming up in v9.3
How to start adopting
MySQL and MariaDB though they share the same roots for replication .They support parallel replication , but they diverge the way the parallel replication is implemented.
Percona Cluster ( Galera ) is one of the best database solution that provides synchronous replication. The feature like automatic recovery, GTID and multi threaded replication makes it powerful along with ( XtraDB and Xtrabackup ).
The good solution for MySQL HA.
Countdown to PostgreSQL v9.5 - Foriegn Tables can be part of Inheritance Tree Ashnikbiz
Distributed databases and horizontal scale up is one of the key demands in today's date. PostgreSQL already had some vertical scaling features and horizontal scale-up by adding disks and table partitioning/child tables. With release of v9.5, PostgreSQL will get basic foundation for native sharing capability. From v9.5 Foreign Tables will be able to participate in Inheritance Tree as a child or parent table i.e. one can have table partitions residing on different system.
In our countdown to v9.5 series of hangouts, we will be covering some of the great features of PostgreSQL v9.5 and what is their real life applicability. In the first hangout in this series we will be talking about-
- The feature of foreign partitions/child tables
- Syntax and usage
- EXPLAIN plan demo
- Use cases and benefits
Join us for more and send us your queries on success@ashnik.com
High performance and high availability proxies for MySQLMydbops
This is presented at LSPE meet up on 17-06-2017.
ProxySQL and MaxScale are the next-generation database proxy that manages security, scalability, high availability and data streaming in scale-out deployments
ProxySQL and MaxScale have been most widely adapted in industry these days. They can be used in smaller platforms to bigger platforms. The Objective of this talk is to make awareness about the next-gen database proxies and their value addition.
Tuning the Memory and Optimizer Parameters - This topic has come quite often in requests and suggestions from our regular viewers and followers of our Postgres Hangouts.
So we picked it up as the topic for this month's Postgres Hangout. This time we will try to explore and share on Memory and Memory .
Join us as we discuss what impacts your decision before you put a number against each of these important parameters!
Technical Introduction to PostgreSQL and PPASAshnikbiz
Let's take a look at:
PostgreSQL and buzz it has created
Architecture
Oracle Compatibility
Performance Feature
Security Features
High Availability Features
DBA Tools
User Stories
What’s coming up in v9.3
How to start adopting
MySQL and MariaDB though they share the same roots for replication .They support parallel replication , but they diverge the way the parallel replication is implemented.
Percona Cluster ( Galera ) is one of the best database solution that provides synchronous replication. The feature like automatic recovery, GTID and multi threaded replication makes it powerful along with ( XtraDB and Xtrabackup ).
The good solution for MySQL HA.
Countdown to PostgreSQL v9.5 - Foriegn Tables can be part of Inheritance Tree Ashnikbiz
Distributed databases and horizontal scale up is one of the key demands in today's date. PostgreSQL already had some vertical scaling features and horizontal scale-up by adding disks and table partitioning/child tables. With release of v9.5, PostgreSQL will get basic foundation for native sharing capability. From v9.5 Foreign Tables will be able to participate in Inheritance Tree as a child or parent table i.e. one can have table partitions residing on different system.
In our countdown to v9.5 series of hangouts, we will be covering some of the great features of PostgreSQL v9.5 and what is their real life applicability. In the first hangout in this series we will be talking about-
- The feature of foreign partitions/child tables
- Syntax and usage
- EXPLAIN plan demo
- Use cases and benefits
Join us for more and send us your queries on success@ashnik.com
Learn best practices for taking advantage of Amazon Redshift's columnar technology and parallel processing capabilities to improve your data warehouse performance.
SQL Server 2014 Extreme Transaction Processing (Hekaton) - BasicsTony Rogerson
Far from Hekaton being an extension of DBCC PINTABLE, it’s a huge new piece of functionality that can significantly improve the scalability of various data based scenarios – not just OLTP but also ETL and real-time BI.
This session will introduce Hekaton features, how and when to use it; it will be demo led giving Hekaton end-to-end: enabling it, create tables, index design, query considerations, native stored procedures, durability [or not], introduce methods of identifying what to put in memory or not.
This presentation speaks about the basic storage engines of MySQL. Their file formats and their usage. Well it does not speak much about InnoDB as it is a very vast topic.
This talk at the Percona Live MySQL Conference and Expo describes open source column stores and compares their capabilities, correctness and performance.
Similar to MySQL Performance Tuning - GNUnify 2010 (20)
High Availability Using MySQL Group ReplicationOSSCube
MySQL Group Replication is a recent MySQL plugin that brings together group communication techniques and database replication, providing both a high availability and a multi-master update everywhere replication solution.
The PPT provide provide a broad overview of MySQL Group Replication plugin, what it can achieve and how it helps keep your MySQL databases highly available and your business up and running, without fail.
Accelerate Your Digital Transformation Journey with PimcoreOSSCube
A key priority for businesses today is to successfully transform their enterprise into a digital business. Digital transformation offers enormous opportunities to enterprises to refine their business models and to win in this digital era. How is your organization placed in this digital world?
In the video, we have discussed, how Pimcore delivered the promise, consolidating PIM, CMS, DAM & Commerce within one framework platform with faster time-to-market.
We will also go through some recent digital transformation experiences driven through Pimcore that helped clients achieve market differentiation and customer value.
Key Points:
* Understanding Digital Transformation need and strategies
* Transformation of digital strategies through Pimcore
* Helps gain insights into Pimcore and its features
* Identification/Co-relation of end customer needs based on our digital transformation experiences
Migrating Legacy Applications to AWS Cloud: Strategies and ChallengesOSSCube
To reduce the TCO of application infrastructure and to make them more scalable and resilient it is advisable to migrate on-premise legacy applications to AWS cloud. In this webinar, you will learn the benefits, key challenges and strategies to mitigate them. It will also talk about leveraging the cloud infrastructure to further modernize the application.
Key Take Away:
Opportunities and challenges while migrating premise application to cloud.
Identifying the applications
Assessing cloud architecture and costs
Data migrations strategies and options
Strategies for migration applications
Leveraging the cloud and optimization
Using MySQL Fabric for High Availability and Scaling OutOSSCube
MySQL Fabric is an extensible framework for managing farms of MySQL Servers. In this webinar, you will learn what MySQL Fabric is, what it can achieve and how it is used by database administrators and developers. Plus, you will learn how MySQL Fabric can help for sharding and high-availability. See more @ http://www.osscube.com/
Webinar: Five Ways a Technology Refresh Strategy Can Help Make Your Digital T...OSSCube
You’ve realized that in order to create new revenue streams, increase efficiency and improve customer engagement your organization may need a digital transformation. But what exactly is a digital transformation, how do you start one, and how does technology play a role? Join experts Dietmar Rietsch, co-founder and CEO of Pimcore, and John Bernard, EVP of North America at OSSCube, as they discuss how Pimcore is disrupting the digital transformation market.
We’ll cover:
- What digital transformation is and why it’s important for your organization
- The role technology plays in the digital transformation process
- How choosing the right technology gives you a competitive advantage
- Outcomes of a successful digital transformation project
The pace of change in business is faster than we could have ever imagined, and in this day and age you must either disrupt, or be disrupted.
This presentation aims to explain the changes we are seeing in the business technology world, the struggles many organizations are facing to keep up, and present the audience with solutions to these difficulties.
The presentation was originally presented by OSSCube CEO Lavanya Rastogi.
Legacy to industry leader: a modernization case studyOSSCube
This live webinar goes through the steps of how MakeMyTrip.com engaged OSSCube to completely modernize their website and help them become one of the top online travel companies in the world. Zend Server and Zend Studio were used to expedite the entire project for what has now become arguably the largest Drupal implementation to date.
This live webinar demonstrates how using an integrated customer acquisition solution can help to close the loop between marketing and sales. We show you examples of how this process has worked for other companies, giving them a better understanding as to where their leads are coming from and how to best spend their marketing dollars for the highest return. - See more at: https://www.osscube.com/webinar/sales-and-marketing-together-at-last#sthash.ZT2dsELD.dpuf
Using pim to maximize revenue and improve customer satisfactionOSSCube
This live webinar shows how Pimcore, an open source PIM (Product Information Management) solution, can be used to quickly update and append your product catalog across all channels, effectively reducing data management costs.
This webinar explores the process of how OSSCube developed a Talend solution--for a global provider of digital marketing and client reporting tools--that aggregates and converts information from a variety of resources into well-defined data formats.
Watch on YouTube: https://www.youtube.com/watch?v=gyZiiG7mjx8
OSSCube EVP John Bernard and Talend Alliances and Channels Manager Rich Searle provide an in-depth explanation of the benefits of Talend as well as the usefulness of data organization in today's business world.
Key Discussion Points:
- Talend ETL tools capabilities
- Implementing Talend in your organization
For more information please visit OSSCube.com
For more webinars please visit OSSCube.com/upcoming-webinars
Follow us on Twitter @OSSCube
Follow us on LinkedIn http://linkedin.com/company/osscube
This webinar goes through how the commerce industry today has changed, causing customers to interact differently, expect more from retailers and demand unique shopping experiences. Rakesh Kumar and John Bernard dive into what makes Magento the world’s leading eCommerce platform and how it puts the retailer back in control.
Non functional requirements. do we really care…?OSSCube
Non Functional requirements are an essential part of a project’s success, sometimes it becomes less focused area as everyone tries to make project successful in terms of functionality. This recorded webinar uncovers what can happen if Non Functional requirements are not addressed properly. What are the after impacts? You also learn the importance of Non Functional requirement, their identification, implementation and verification.
Learning from experience: Collaborative Journey towards CMMIOSSCube
Are you planning to start CMMI Initiative? Or already a part of this journey? In this recorded webinar, we share our CMMI Implementation experience. You learn what were key factors and challenges faced during each phase. This webinar also sheds some light on how we made this journey a collaborative one.
JXL is the library of JExcel API, which is an open source Java API that performs the task to dynamically read, write, and modify Excel spreadsheets.
We can use its powerful features to build an automated testing framework using Selenium Web Drivers. The JXL works as a data provider where multiple sets of data is required as input. Moreover, users can read and write information using external excel files. The JXL also helps create custom reports where users have all authority to design reports as per their need.
Listen to this webinar to explore JXL with examples.
New to cloud computing? This recorded webinar helps you understand cloud capabilities and how it has made easier server deployment, infrastructure planning and capacity planning. This webinar takes you through an introduction to AWS components and how you can decide and design the best environment for your business.
Maria DB Galera Cluster for High AvailabilityOSSCube
Want to understand how to set high availability solutions for MySQL using MariaDB Galera Cluster? Join this webinar, and learn from experts. During this webinar, you will also get guidance on how to implement MariaDB Galera Cluster.
Talend Open Studio Introduction - OSSCamp 2014OSSCube
Talend Open Studio is the most open, innovative and
powerful data integration solution on the market today. Talend Open Studio for Data Integration allows you to
create ETL (extract, transform, load) jobs.
JobQueue is one of the feature of Zend Plateform. Where you can schedule and manage the execution of php scripts (jobs). The Job Queue can be used to create asynchronous execution of php script and provide, for instance, the scalability of a server.
application
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
Here is something new! In our next Connector Corner webinar, we will demonstrate how you can use a single workflow to:
Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Let's dive deeper into the world of ODC! Ricardo Alves (OutSystems) will join us to tell all about the new Data Fabric. After that, Sezen de Bruijn (OutSystems) will get into the details on how to best design a sturdy architecture within ODC.
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
15. EXPLAIN Types
system
The table has only one row
const
At the most one matching row, treated as a
constant
eq_ref
One row per row from previous tables
ref
Several rows with matching index value
ref_or_null
Like ref, plus NULL values
index_merge
Several index searches are merged
unique_subquery
Same as ref for some subqueries
index_subquery
As above for non-unique indexes
range
A range index scan
index
The whole index is scanned
ALL
A full table scan
16. EXPLAIN Extra
Using index
The result is created straight from the index
Using where
Not all rows are used in the result
Distinct
Only a single row is read per row combination
Not exists
A LEFT JOIN missing rows optimization is
used
Using filesort
An extra row sorting step is done
Using temporary
A temporary table is used
Range checked
for each record
The read type is optimized individually for
each combination of rows from the previous
tables
17. Optimizer Hints
STRAIGHT_JOIN
Forces the optimizer to join the tables in the
given order
SQL_BIG_RESULTS
Together with GROUP BY or DISTINCT
tells the server to use disk-based temp
tables
SQL_BUFFER_RESULTS Tells the server to use a temp table, thus
releasing locks early (for table-locks)
USE INDEX
Hints to the optimizer to use the given
index
FORCE INDEX
Forces the optimizer to use the index (if
possible)
IGNORE INDEX
Forces the optimizer not the use the index
18. Selecting Queries to Optimize
• The slow query log
– Logs all queries that take longer than
long_query_time
– Can also log all queries that don’t use indexes
with
--log-queries-not-using-indexes
– To log slow administrative commands use
--log-slow-admin-statements
– To analyze the contents of the slow log use
mysqldumpslow
19. • The general query log can be use to analyze:
– Reads vs. writes
– Simple queries vs. complex queries
– etc
23. Choosing Best Suited Storage Engine
• Understanding benefits and drawbacks of
each storage engine is very important while
designing application.
• Different storage engine has different index
capability ,application need should be kept
in mind while choosing storage engine
25. InnoDB-Specific Optimizations
• InnoDB uses clustered indexes
– The length of the PRIMARY KEY is extremely
important
• The rows are always dynamic
– Using VARCHAR instead of CHAR is almost always
better
• Maintenance operations needed after
– Many UPDATE/DELETE operations
• The pages can become underfilled
30. Tuning MySQL Parameters
• Some MySQL options can be changed online
• The dynamic options are either
– SESSION specific
• Changing the value will only affect the current
connection
– GLOBAL
• Changing the value will affect the whole server
– Both
• When changing the value SESSION/GLOBAL
should be specified
31. • Online changes are not persistant over a
server restart
– The configuration files have to be changed as well
• The current values of all options can be found
with
SHOW SESSION/GLOBAL VARIABLES
34. Query Cache
• Stores SELECT queries and their results
• Purpose: improve performance for
frequently requested data
• The data in the query cache is invalidated as
soon as a modification is done in the table
• Controlled with the query_cache_size
variable
35. • The Qcache_% status variables help
monitoring the cache
– The utilisation ratio: Qcache_hits vs.
Com_select
• The query cache can be emptied with
RESET QUERY CACHE
36. Some Thread Specific Options
• read_buffer_size (default 128Kb) and
read_rnd_buffer_size (default 256Kb)
– Size of cache used for table scanning
– Not equivalent to block size
• The database is not divided into blocks but directly into
records
– Increase if you do many sequential scans
• sort_buffer_size (default 2Mb)
– Size of the GROUP BY / ORDER BY cache
– If more memory is needed it will be taken from the disk
• tmp_table_size (default 32Mb)
– Limit after which temporary tables will not be MEMORYs
anymore, but MyISAM tables
37. Some Global Options
• table_cache (default 64)
– Cache for storing open table handlers
– Increase this if Opened_tables is high
• thread_cache (default 0)
– Number of threads to keep for reuse
– Increase if threads_created is high
– Not useful if the client uses connection pooling
38. • max_connections (default 100)
– The maximum allowed number of simultaneous
connections
– Very important for tuning thread specific memory
areas
– Each connection uses at least thread_stack of
memory
39. MyISAM Global Options
• key_buffer_size (default 8Mb)
– Cache for storing indices
– Increase this to get better index handling
– Miss ratio
(key_reads/key_read_requests) should
be very low, at least < 0.03 (often < 0.01 is
desirable)
• Row caching is handled by the OS
40. MyISAM Thread-Specific Options
• myisam_sort_buffer_size (default
8Mb)
– Used when sorting indexes during
REPAIR/ALTER TABLE
• myisam_repair_threads (default 1)
– Used for bulk import and repairing
– Allows for repairing indexes in multiple threads
• myisam_max_sort_file_size
– The max size of the file used while re-creating
indexes
41. InnoDB-Specific Optimization
• innodb_buffer_pool_size (default
8Mb)
– The memory buffer InnoDB uses to cache both
data and indexes
– The bigger you set this the less disk i/o is
needed
– Can be set very high (up to 80% on a dedicated
system)
42. • innodb_flush_log_at_trx_commit
(default 1)
– 0 writes and sync’s once per second (not ACID)
– 1 forces sync to disk after every commit
– 2 write to disk every commit but only sync’s about
once per second
43. InnoDB-Specific
Optimization
• innodb_log_buffer_size (default
1Mb)
– Larger values allows for larger transactions to be
logged in memory
– Sensible values range from 1M to 8M
• innodb_log_file_size (default 5Mb)
– Size of each InnoDB redo log file
– Can be set up to buffer_pool_size
45. Thank you for your time and attention
www.osscube.com
For more information, please feel free to drop in a line to
sonali@osscube.com or visit http://www.osscube.com
Editor's Notes
NEW/UPDATED
UPDATED
changed sort_buffer to sort_buffer_size (typo? or change to variable?)
added defaults