MySQL 8.0 performance degradation compared to 5.7 (2 replies)
I realize there are many threads on this subject, and I've read as many as looked relevant and noted the suggestions and findings, and decided to post for help with our specific use case. We are...
View ArticleUnderstanding Serializable Isolation Level (no replies)
from the docs: https://dev.mysql.com/doc/refman/8.0/en/innodb-transaction-isolation-levels.html SERIALIZABLE This level is like REPEATABLE READ, but InnoDB implicitly converts all plain SELECT...
View ArticleMigration from MAaria-db (no replies)
Hi, We have migrated our db (for poc) to Aurora my sql based on 8.0.23 and we are facing huge performance issues where we see my sql doesn't use the correct indexes. We can't change the whole code to...
View ArticleSysbench fileio (no replies)
HI, I am running sysbench fileio for mysql with below command ./sysbench fileio --file-total-size=10G --file-test-mode=rndrw --time=300 --mysql-db=mysql --mysql-host=localhost --mysql-user=root...
View ArticleTIME_WAIT (no replies)
On a windows 2022 server running an application (website) the pulls data from a Mysql database. the site stops responding, I run a netstat- a on the windows server to see over 40 of them : TCP...
View ArticleTimeout of Simple Query - Makes no sense (no replies)
We have a system that builds dynamic SQL based on selections made by the front-end. It works great (overall), but there appears to be an issue with what should be a simple query that times out. Here...
View ArticleSlow query in a view, how to improve it (similar to putting indexes?) (no...
Hi everyone! I made quite a complex View on my MySQL database, and I realized that some queries are slow. My first idea was to add indexes but it's not possible to do on a view so I'm lost on how to...
View ArticleQuery not properly using indices (no replies)
Hello everyone, I'm currently facing some challenges on column indexation and I would love to get some help. I have trimmed down the problem a lot to illustrate the issue better and it goes like this:...
View ArticlePerformance issue in MYSQL 5.7 (no replies)
Hello Everyone, I am facing performance issue in my query , My table contains 28278163 this many no.of rows. Problem:- My query is using one default index it self. I created proper index for my query,...
View ArticleQueries in creating index (1 reply)
Hello Everyone, I have a doubt in creating index which is my sql query contains id, name, age columns in where clause , so i am trying to create index on this respective columns but my index is not at...
View ArticleMySQL Telemetry Tracing with OCI APM (no replies)
MySQL Telemetry Tracing with OCI APM - https://blogs.oracle.com/mysql/post/mysql-telemetry-tracing-with-oci-apm
View ArticleHyphen in FULLTEXT (3 replies)
Table have 26 milj rows, 2,3GiB (simple key, value table). InnoDB. When i do query with hyphen, query is really slow (3sec). Every other query run smootly. What can I do to fix this? Examples: SELECT...
View Article100x to 200x InnoDB performance degradation MySQL 5.7 -> 8.0.36 ? (no replies)
Hi, I've posted in the newbies forum, because I'm completely new to MySQL 8.0 specifically (I have experience with MySQL 5.7) and have developed over 400 web apps and websites using MySQL over the...
View ArticleJSON insert performance (no replies)
Hi, We plan to store JSON documents in MySQL 8.0 The documents are pretty simple: max 25 attributes, with short values. Are there any performance benchmarks? What is the maximum throughput that can be...
View ArticleMysql 5.7 -> 8.0 migration (2 replies)
Hey there Recently we've been working on migration from mysql 5.7 to mysql 8.0 and after migration we found that performance for some endpoints has been degradaded. For the context, we have a cluster...
View ArticleRe: MySQL 8.0 performance degradation compared to 5.6 (no replies)
We recently upgraded from MySQL 5.6 to MySQL 8.0.36. We've noticed a significant drop in performance. A query that previously took 2 minutes to execute in MySQL 5.6 is now taking 5 minutes in MySQL...
View ArticleIncredibly slow count(*) on MariaDB / MySQL (1 reply)
Problem: SELECT COUNT(*) FORM contact_activity takes ~6 minutes Profiling the query shows 100% of the time is spent over 'sending data' although it's only the count that is returned, no other data, no...
View Articlequery is super slow until either i remove one particular JOIN or the ORDER BY...
Here's my query: SELECT * FROM calls ca JOIN conferences co ON ca.conference_id = co.id JOIN conference_participants p ON co.id = p.conference_id AND p.caller_id IN ('group:40') WHERE ca.duration...
View Articleinter-region data import speed issue (no replies)
Hi, A MySQL database dump is located on an AWS EC2 instance in the us-east-1 (N.Virginia) region (ec2-use1). The RDS instance is located in the ap-southeast-2 (Sydney) region (rds-apse2). I use the...
View ArticleVariable time execution for INSERT (no replies)
Hello, I do an INSERT in a table who has around 1 million rows in MySQL 8.0. I don't know why I have different execution times for the same data to insert. For example, I measure one time 281...
View ArticleFlex MySQL 8.0 on AzUre (3 replies)
This is probably an Azure question but i can't get a sensible response from MS. Did anything change on Azure's memory management for MariaDB and MySQL in the last few months? I'd been running 5...
View ArticleMySQL thread_stack vs memory usage (no replies)
Hey all, I run a MySQL8 DB on AWS RDS. Recently, I got a request to increase thread_stack by around 20%. While testing it on lower environments, I noticed that the DB memory usage decreased (freeable...
View ArticleAnalyzing sql query performance issues (no replies)
Hello, I have few questions in regards to query performance tuning. (Note- its version 8.0.32) 1) I understand we use "explain analyze" to see the execution plan and it shows the exact resource...
View ArticleWhy do users report a performance decline in 8.0? (4 replies)
Many users claim that the performance of 8.0 has declined, but this is a misconception, often based on simple sysbench test results. Users should test our open-source version in real-world...
View ArticleMySQL: New JSON format for EXPLAIN (no replies)
MySQL: New JSON format for EXPLAIN - https://blogs.oracle.com/mysql/post/new-json-format-for-explain
View ArticleDuplicate buckets in event_statements_histogram_by_digest (no replies)
Hi, I am hoping to use the event_statements_histogram_by_digest table to extract histogram data about my queries - so that I can calculate quantiles (above what is available in...
View ArticleSQL Performance with sysbench on different disks (no replies)
Hello everybody, I have some problem about performance with sysbench on my different OVH servers, here are my results : With this command : sysbench --test=fileio --file-test-mode=seqwr run RISE-2...
View ArticleMySQL running VERY slowly on a new i9 machine. Ideas or advice? (1 reply)
Hello All: I have been using MySQL 8.0.26 on my i7 Dell Inspiron laptop for about 5 years (full specs below). Last week, I purchased some upgraded hardware for an important project: An i9 CyberPowerPC...
View ArticleMySQL Workbench username (?!?), SSL CA (?!?) (no replies)
I am studying for my third SQL certification on Coursera. It requires downloading the "Connecting to Mode Analytics - Updated.pdf" (MODE: https://mode.com/), which on page 5 provides the option to...
View ArticleRefresh MySQL on RDS Amazon (no replies)
Hi Experts, Iam a Microsoft sql server dba, currently taking task on MySQL on AWS RDS. I have a question how do we refresh Database from Production to Developemtn environment.If i take export the...
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