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8 votes

Understanding IXSCAN and COLLSCAN in MongoDB logs

I'm attempting to grep through some Mongo logs in an attempt to find slow operations that I need to optimize. Slow query logging is at the default and is logging operations over 100ms. Rather than ...
Stennie's user avatar
  • 1,290
6 votes

How to improve AWS RDS Performance - Heavy read write updates

I'm going to turn my comments above into an answer. T2 instances only get a fraction of a CPU - 10% for a t2.micro, 40% for a t2.medium. You get CPU credits that build up, but once you use them you ...
Tim's user avatar
  • 33.1k
4 votes

What does "GC (Allocation Failure)" mean in my ElasticSearch 5.6 logs?

GC (Allocation Failure) is a JVM message (not an Elasticsearch-specific one) that can be a sign that there's memory pressure, but it's not catastropic to the JVM (that would cause a OutOfMemoryError ...
Wesley's user avatar
  • 32.9k
4 votes

MySQL LOAD DATA INFILE: Better Server, Worse Performance

Here's what seems to have been causing this behavior: Per the Azure documentation, the Basic tier server on Azure comes with "variable" IOPS whereas the Memory Optimized server comes with a fixed ...
user3175864's user avatar
4 votes

One user for all databases or different user for different databases?

Performance is not relevant, use one user per website for both traceability and security, that way if you ever get any performance issues you can more easily track which site it relates to.
NiKiZe's user avatar
  • 1,316
4 votes

How to improve AWS RDS Performance - Heavy read write updates

Take note of the disk bottleneck : Disk IOPS. RDS will throttle IO request if it is not provisioned. There is 3iops/GB given to SSD. So if you have 100GB allocated for SSD, you can max up 3x100 = 300 ...
mootmoot's user avatar
  • 304
3 votes

Regarding how Big companies set up their databases

Even relatively small servers are capable of executing hundreds of queries per second. Therefore I think that a first, major bottleneck is caused by improper tuning of your Postgres instance. There ...
fvu's user avatar
  • 686
2 votes

RAID 0 for Development

Complete a backup restore test during the day. Destroy the storage volumes to simulate RAID 0 storage pool failure, which will take the test systems down. Copy from backup media, and complete a ...
John Mahowald's user avatar
2 votes

Slow database connection with KVM

Your VM is emluating an rtl8139 NIC, a 10/100 Mbps device from the mid-1990s. This driver is only present so that KVM can allow ancient operating systems to connect to the network. For modern ...
Michael Hampton's user avatar
1 vote

MYSQL: Many slave servers with smaller resources or less with larger resources

It depends. The most likely thing to adjust in hardware is RAM. If you tune innodb_buffer_pool_size to about 70% of RAM and that is bigger than the size of all the data, then there will be very ...
Rick James's user avatar
  • 2,618
1 vote

Proof CPU maximum frequency in VM

It is totally possible for TurboBoost be enabled while, at the same time, hypervisor only reporting the base CPU frequency. However, it is unlikely that you will ever enjoy the 3.6 GHz boosted ...
shodanshok's user avatar
1 vote

Can SQL Server 2019 perform equally well under Linux and Windows (same hardware)?

I advise you to take a look at for performance best practices and configuration guidelines ...
r3d's user avatar
  • 148
1 vote

Mysql high cpu usage (over 600%)

Suggestions for your my.cnf [mysqld] section changes. key_buffer_size=100M # from 1G for more reasonable RAM allocation thread_cache_size=100 # from 8 to reduce threads_created REMOVE THE leading #...
Wilson Hauck's user avatar
1 vote

MariaDB 10.3 CPU usage, Server performance suggestions

Suggestions to consider for your my.cnf OR my.ini [mysqld] section (RPS = Rate Per Second) # 20180901 1346 from # log_error=/var/lib/mysql/2cd908c24352-error.log # from default ...
Wilson Hauck's user avatar
1 vote

MySQL: view read/write proportion, per specific table

You cannot look at the tables once and determine which ones are write heavy, and this is especially so if the database has been up and running for any considerable time. Due to changing usage patterns,...
dland's user avatar
  • 125
1 vote

SQL Server Express for Production Databases?

It can certainly be used for significant production applications. We have used it at over 1500 healthcare clinics all with separate SQL Server Express instances installed to process millions of ...
pacificwinter's user avatar
1 vote

Best database (SQL\NoSQL) for storing file hashes and corresponding description

Assuming the hash key is fixed or small sized, and the description don't go over certain limits beyond ordinary text, any relational or noSQL database with adequate indexing will do. The search speed ...
Yusuf N's user avatar
  • 141
1 vote

MySQL bottleneck on AMD A-10 witn 12BG of RAM?

Try tuning the MySQL performance settings. If there is any issue with the performance settings then you may face this issue. You can also try disabling vacuum. Single record per second is very low. We ...
Paventhan's user avatar
1 vote

Are the limitations of SQL Server Express the bottleneck?

as you stated the application is running for very long time, so I'd assume that the usability and volume of usage has changed since then, which could cause the performance degradation. SQL Express ...
Everton Oliveira's user avatar
1 vote

connections to postgresql at particular time frame

I am not sure if I understand your problem correctly but generally speaking PostgreSQL so far ( pg 9.6 2016/12) does not show any history of these statistics. Therefore I use monitoring with ...
JosMac's user avatar
  • 131
1 vote

Mysqld.exe RAM size increasing upto 130MB and performance is poor

Relational database servers will (in every case I've worked with) consume all available RAM in the system to cache and optimize search algorithms. You can specify upper limits on how much it is ...
TheCompWiz's user avatar
  • 7,399
1 vote

How to improve AWS RDS Performance - Heavy read write updates

I ended up creating a c4.xlarge EC2 and having it operating as my MariaDB 10 server. Due to the large amount of traffic currently and a major increase coming with new marketing campaigns I could not ...
Steven K7FAQ's user avatar

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