morgo

14 ms·

91.
by morgo 9y ago
I believe the answer is "yes" but this problem is not unique to semi-sync. Take a single server example: You could ask the database to "COMMIT"; it receives the command and processes it, but does not manage to send you
92.
by morgo 9y ago
This was the case for 5.5 and 5.6. MySQL 5.7+ will default to wait for the ack before committing locally: https://dev.mysql.com/doc/refman/5.7/en/server-system-variab...
93.
by morgo 9y ago
MySQL 5.7+ will default to wait for the ack before committing locally. This is referred to as "lossless semi-sync".
94.
by morgo 9y ago
Nope, it's planned though. In the mean time, I recommend using something like ProxySQL to route based on schema to shard between multiple instances of MySQL.
95.
by morgo 9y ago
The three node minimum is to avoid split brains. You can still access the data with fewer (for recovery etc.) but the cluster is not HA. Read throughput will go up by being able to distribute reads amongst the cluster. Write throughput sh
96.
by morgo 9y ago
In single primary the other nodes are put in a read-only mode so they can not accept writes. So stale reads can not happen. To expand on your question a little - the MySQL router currently works better for single primary (it supports mult
97.
by morgo 9y ago
We do not have current plans for an AWS CloudFormation template. QA has definitely been one of the harder parts of creating a distributed MySQL. I don't work closely enough on that part to answer this question. Sorry!
98.
by morgo 9y ago
I'm not sure it is quite the same, since it is WAL based (i.e. can you write to any node?) There is semi-sync in MySQL as well, which ensures N replicas have received a write.
99.
by morgo 9y ago
(See my other reply)
100.
by morgo 9y ago
Very similar concept, but differences are well described here: http://lefred.be/content/group-replication-vs-galera/ The Tl;dr I give most people is that the Group Replication technology (innodb cluster) uses Paxo
101.
by morgo 9y ago
Hi! I'm a Product Manager for the MySQL Server. I don't specifically work on InnoDB Cluster, but am happy to answer questions. Let me start of by describing how the clustering works: - A cluster is 3+ nodes in a group, each with
102.
by morgo 10y ago
Product Manager for the MySQL Server here - I would like to re-enforce a good point you mention: quirks can be a side-effect of making sure you have a good upgrade story. Sure; we would prefer not to have them, but you want a vendor which
103.
by morgo 10y ago
From MySQL 5.6 to MySQL 5.7, the cost model changes significantly. So while most queries will improve - there are edge cases where regressions occur. In anticipation of this occurring (even if you are better 99% of the time; there will be
104.
by morgo 10y ago
Strict has been the default since MySQL 5.7. The default character set switches to utf8mb4 in MySQL 8.0.
105.
by morgo 10y ago
My goal is to explicitly state something as "new" when it is first in 8.0; but not mention the version when referring to older (mostly because it makes readability harder). So you can see the invisible indexes page does this (8.0
106.
by morgo 10y ago
It has not passed New Feature Qualification[1] yet, which has to be done before it can be merged to trunk. You can see the state of it from a presentation earlier this month: https://www.slideshare.net/DagHWanvik/sql-w
107.
by morgo 10y ago
Author here. Thanks for linking to my guide :) I'll be expanding it in the coming months as the new features in MySQL 8.0 are released. On my TODO is descending indexes, improvements to OPTIMIZER TRACE, Window functions, CTEs and exp
108.
by morgo 10y ago
Author here - some of it applies to all databases generically (performance characteristics of a B+tree and cost-based optimization). But MariaDB diverged from MySQL 5.5 (2010); so there is a lot which is different.
109.
by morgo 10y ago
Author here (and product manager for MySQL). We do not have a date yet for MySQL 8.0, but it is coming closer. We are on a ~2-3 year release cycle with 5.7 released Oct 2015. Many of the features of this guide are now specific to MySQL. M
110.
by morgo 10y ago
Author here - Yes, I agree with you on re-use of the index. This is sort of left-most rule, but I should really break it out into its own point.
111.
by morgo 10y ago
Author here. Yes - the text right above this says that: "Determining the correct order of columns in a composite index is tricky. Here are some considerations to be aware of .." I think myth is a strong word. It holds truth, but
112.
by morgo 10y ago
https://dev.mysql.com/doc/refman/5.5/en/index-merge-optimiza...
113.
by morgo 10y ago
The limit of one index per query was lifted in 2005, with mysql 5.0.
114.
by morgo 10y ago
This is only true for one specific kind of cache (query cache) which has been disabled by default for 4 years now. It works well at cheating benchmarks, and masking un-optimized queries. It is not something that I would recommend.
115.
by morgo 10y ago
I have a guide that shows the equivalent for MySQL. It's kind of split between these two pages: http://www.unofficialmysqlguide.com/introduction.html http://www.unofficialmysqlguide.com/server-architec
116.
by morgo 10y ago
It is most likely appearing to work without a password because it is using socket authentication (vs tcp). See: http://mysqlserverteam.com/secure-by-default-in-mysql-5-7/ If you want to double check, try 'mysql -
117.
by morgo 10y ago
It is much harder to do this with MySQL. The default is now a randomly generated password. You have to overwrite it with --initialize-insecure if you want to setup with a blank password.
118.
MySQL Group Replication: It’s in 5.7.17 GA(mysqlhighavailability.com)
4 points by morgo 10y ago|1 comments
119.
by morgo 10y ago
In future I intend to expand it for MySQL 8.0. (I am the Product Manager for the MySQL Server, but yes - I personally own the domain.)
120.
by morgo 10y ago
It's important to distinguish between cases where it is slower, and cases where query plans change. MySQL 5.7 changed the cost-model significantly, so while it will be better on most queries, there are cases where two-wrongs-made-a-rig

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