Hello ,
I have two production servers worth around 100 GB.I have to setup
multi-source replication to a single slave for these servers.My
preferable method of backup is percona xtrabackup or enterprise
backup.Could you please guide how can i restore the backup to
from these two master servers to the slave ?
In this blog post, we’ll look at how ZFS affects MySQL performance when used in conjunction.
ZFS and MySQL have a lot in common since they are both transactional software. Both have properties that, by default, favors consistency over performance. By doubling the complexity layers for getting committed data from the application to a persistent disk, we are logically doubling the amount of work within the whole system and reducing the output. From the ZFS layer, where is really the bulk of the work coming from?
Consider a comparative test below from a bare metal server. It has a reasonably tuned config (discussed in separate post, results and scripts here). These numbers are from sysbench tests on hardware with six SAS drives behind a RAID controller with a write-backed cache. Ext4 was configured with RAID10 softraid, while ZFS …
[Read more]Today, let’s have a look at the TOP 10 new features in MySQL 8.0 that will improve DBA’s life.
To shrink the list to 10 only items wasn’t an easy task, but here is the top 10:
- Temporary Tables Improvements
- Persistent global variables
- No more MyISAM System Tables
- Reclaim UNDO space from large transactions
- UTF8 performance
- Removing Query Cache
- Atomic DDLs
- Faster & More Complete Performance Schema (Histograms, Indexes, …) and Information Schema
- ROLES
- REDO & UNDO logs encrypted if tablespace is encrypted
Temporary Tables Improvements
Since 5.7, all internal temporary tables are created in a unique shared tablespace called “ …
[Read more]Since January 2017, the MySQL Replication Team has been involved in processing many Community Contributions !
We are really happy to receive contributions (and not only in the replication team), but this also implies a lot of work from our engineers, as more than resolving a bug or developing a new feature, code contributions need to be analyzed, the code needs to be understood and validated.…
With support of multi-threads replication starting from MySQL 5.7, the operations on slave are slightly different from single-thread replication. Here is a list of some operation tips for the convenience of use as below:
1. Skip a statement for a specific channel.
Sometimes, we might find out that one of the channels stop replication due to some error, and we may want to skip the statement for that channel so that we can restart a slave for it. We need to be very careful not to skip the statement from the other channel, since the command SET GLOBAL sql_slave_skip_counter = N is for global. How can we make sure the global sql_slave_skip_counter is applied to a specific channel and not to the other channel? Here are the steps:
1.1: Stop all slaves by: stop slave;
stop slave;
1.2: Set up the count of statement to skip by: SET GLOBAL sql_slave_skip_counter = N;
SET GLOBAL …[Read more]
Whenever we do upgrades for our clients from one major version of MySQL to another we strongly recommend to test in two forms.
First, it would be a performance test between the old version and the new version to make sure there aren’t going to be any unexpected issues with the query processing rates. Secondly, do a functional test to ensure all queries that are running on the old version will not have syntactic errors or problems with reserved words in the new version that we’re upgrading to.
If a client doesn’t have an appropriate testing platform to perform these types of tests, we will leverage available tools to test to the best of our ability. More often than not this includes using pt-upgrade after capturing slow logs with …
[Read more]Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.
In case you missed last week’s column, don’t forget to read the fairly lengthy FOSDEM MySQL & Friends DevRoom summary.
From a Percona Live Santa Clara 2018 standpoint, beyond the tutorials getting picked and scheduled, the talks have also been picked and scheduled (so you were very likely getting acceptance emails from the Hubb.me system by Tuesday). The rejections have not gone out yet but will follow soon. I expect the schedule to go live either today (end of week) or early next week. Cheapest tickets end March 4, so don’t …
[Read more]Calling all developers, DBAs, engineers, SREs, and database aficionados: we’re hitting the road and hope to see you along the way. It's always a highlight of our year when we get to meet up with our users and friends face-to-face, and we'll be attending events across the country (and abroad!) for the rest of 2018. If you see our booth, come say hello.
Below is a list of the places you'll be able to find us over the next nine months, plus descriptions of how we'll be involved at each event (and, in some cases, special ticket discount codes).
Event | Start | End | Location |
---|---|---|---|
… |
In this blog, I will provide answers to the Q & A for the Troubleshooting MySQL Crashes webinar.
First, I want to thank everybody for attending our January 25, 2018, webinar. The recording and slides for the webinar are available here. Below is the list of your questions that I was unable to answer fully during the webinar.
Q: I have the 600 seconds “Long semaphore wait” assertion failure / crashing issue following DDL queries, sometimes on the master, sometimes just the slaves. Any hints for troubleshooting these? How can I understand what semaphore holding …
[Read more]As part of building an enterprise DW for one of our customers we had to sync a bunch of tables from a MYSQL slave to BigQuery at 30 min intervals. Considering the range of other non-relational data sources which will be part of the this load, we chose Matillion as ETL tool. Matillion is easy to setup (just provision the VM and start authoring jobs) and long list of integrations so it made sense.
This post explains building a Matillion job that does the following:
- Full Load
- Incremental load for tables with larger row count and an ID that can be looked up for new rows since last load.
MYSQL Drivers
If you came from a Google search looking for Matillion — I am assuming you are done with provisioning the instance, setting up default project etc are done, so I am skipping those. While Matillion ships with PostgreSQL drivers, for some reason it doesn’t have MYSQL …
[Read more]