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1
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2answers
391 views

InnoDB Buffer pool hit rate missing from engine status output

I want to check the buffer pool hit rate for InnoDB on MySQL but when I query the database the hit rate seems to be gone from the results: Using query: SHOW ENGINE INNODB STATUS\G ...
0
votes
0answers
14 views

25.000+ rows - MySQL SELECT consecutive numbers performance issue [migrated]

I have tried to be as explicit as I could. Below you have the query explained in details What I want to obtain? - I want to SELECT start_number and end_number from a set of consecutive numbers ...
1
vote
1answer
177 views

Slow connection to Azure Sql Server

I'm moving from a Rackspace Cloud platform to Azure but I'm having some real performance issues. It seems like everything is a little but slower but especially database interaction. I've done some ...
0
votes
2answers
63 views

MySQLD is using 175% of the cpu

On one of the servers, I have mysqld running as slave DB. The CPU usage is 175% at the moment used by mysqld. Here are the results of SHOW PROCESSLIST; ...
0
votes
0answers
67 views

Why is my TPS/TPM value so different between benchmark factory and HammerDB?

I am using both benchmark factory and HammerDB to generate load against an Oracle 12 database. In both cases I use the same DB on the same storage. In both cases I use a warehouse size of 100. When ...
3
votes
1answer
26 views

SQL Server 2005 global slowdown

Two days ago our production server suffered a massive slowdown where the primary symptom was that an extraordinarily high number of requests were suffering SQLTimeouts. I will quickly describe our ...
-1
votes
1answer
122 views

Innodb performs IO Operation when idle

I am currently doing some stress testing where I am pushing inserts to the database as fast as I can. The simulation inserts 10000 records per second. After inserting around 200 million records I ...
7
votes
4answers
8k views

postgreSQL vs Cassandra vs MongoDB vs Voldemort?

Which database to decide upon? Any comparisions? Existing: postgresql Issues Not easily scalable horizontal. Needs sharding etc Clustering does not solve the data growth problem ...
0
votes
1answer
73 views

Is Amazon RDS overkill for small business site?

One of my clients wants a small business site run on Wordpress. I'm setting it up through Amazon EC2, and was curious if using Amazon's RDS service to run the wordpress installation is overkill. I ...
2
votes
0answers
63 views

Exchange 2010 on KVM - CPU usage reporting incorrectly

Good Morning, I have virtualized an exchange server using KVM (proxmox actually). It is Exchange 2010 SP3 running on server 2012 R2. KVM version 1.7.1. I am using the latest (0.1-74) virtio ...
2
votes
1answer
188 views

MongoDB 100% locked periodically. MMS charts attached

Trying to diagnose what could be causing intermittent lock-up on MongoDB server running behind a Rails application. Hoping that someone might recognise the pattern of peaks and troughs in the charts ...
1
vote
0answers
345 views

MongoDB Performance Troubleshooting

I have a small MongoDB replica set (2.4.6) and it seems about once a week, the primary gets bogged and the load average spikes up. This app doesn't see a huge amount of traffic. It resides in EC2 ...
0
votes
1answer
24 views

Over 100% of stage done during DROP COLUMN

I'm running a DROP COLUMN on the primary key column (I know, it's terrible but I had to do it). There's a progress indicator: Stage: 1 of 2 'copy to tmp table' 107% of stage done I haven't been ...
0
votes
3answers
92 views

Development DB server with dedicated hardware [duplicate]

I'm planning to move one of my development database servers to its own machine. I'm currently running it on my laptop, which is not very convenient. DB Servel is PostgreSQL 9.0.1, OS is Gentoo. ...
-1
votes
1answer
37 views

SQL Server Express 2008 R2 limitations

When considering to use an Express Edition of SQL Server 2008 for a system that officially is only tested with full editions, what do I need to know about the limitations? Memory, connections? What ...
0
votes
1answer
667 views

How to set MySQL's internal time zone support?

Today MySQL at Facebook posted the following about MySQL performance: Today we found a performance problem in a completely unexpected place - if TIMESTAMP data type is being used and MySQL is ...
0
votes
1answer
19 views

OpenBase server database connection troubleshoot?

I am troubleshooting a workstation/server instance in which an application hangs while interacting with our Windows 2003 Server OpenBase-hosted database. In short, the application will go into "Not ...
0
votes
1answer
60 views

Database server's Load reaches very high values while nothing seems to use CPU, what could be the reason?

top - 16:33:08 up 155 days, 6:05, 5 users, load average: 27.93, 35.31, 31.34 At this moment it only shows 27.0 but the behavior is like so: While mysqld uses 0% cpu the load raises to high values ...
3
votes
2answers
1k views

Too much I/O generated by postgres stats collector process

I am using XenServer with several virtual machines having local postgres databases. Even when all applications are unused and the databases are idle, each vm causes constant storage network traffic ...
0
votes
1answer
1k views

MongoDB Locking - Very, very, slow to read

This is the output from db.currentOp(): > db.currentOp() { "inprog" : [ { "opid" : 2153, "active" : false, "op" : "update", "ns" : "", ...
3
votes
1answer
3k views

Maintenance of tables: do I need to REINDEX a table after truncating and repopulating?

I have a table with about 2 million rows in it of transactional data that we use for analytics. Every week we reload this with new data, so we've been using TRUNCATE to clear it out and then inserting ...
0
votes
2answers
47 views

No. of databases or no. of tables?

I am running three different sites with ImpressPages CMS v 2.6.. ImpressPages is built on PHP 5.3 and MySQL 5. Each site have about 33 MySQL tables and the databases is using MyISAM engine. I have ...
3
votes
3answers
2k views

Speeding up SQL Server temp table processing with a RAM Disk

A system we are developing consists of a Web app frontend, and a backend that does a lot of data processing using stored procedures in SQL Server 2008 R2 (please, don't ask why...). These stored ...
0
votes
0answers
95 views

Disk IO slower when outstanding IO requests are less than 32

I moved the databases from one server to another and general remark from users is that its slower. The old server was on windows 2003,64 bit, SQL 2005 Ent edition(32 bit) whereas new one is Windows ...
0
votes
2answers
155 views

Postgresql performance enhancement

I have my setup like this: Two separate instances of the database on a clustered environment. Both instances are on dedicated servers each carries up to the standard configurations. Instance one ...
1
vote
1answer
263 views

How can I tell if I would benefit from upgrading my Amazon RDS instance?

I have several sites with very high traffic - all hosted on Heroku and all of which access a db.m1.large mySQL Amazon RDS instance - and would like to know if there would be a performance benefit in ...
1
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2answers
1k views

How to install Sphinx on CentOS 6 where the DB and App server are separate servers

First what is the best way to install Sphinx on a centOs server rpm -ivh http://sphinxsearch.com/downloads/accept.php?file=sphinx-2.0.6-1.rhel6.x86_64.rpm yum install sphinx didn't seem to work. ...
0
votes
1answer
367 views

mysql database config optimization

Have a heavily trafficed database running mostly innodb and would like to better optimize the mysql config. Server has 32Gb ram and the biggest tables are ~18Gb innodb. I think I have done all the ...
0
votes
2answers
200 views

PostgreSQL, automate REINDEX, Windows environment

I have a couple of PostgreSQL tables (9.1) which are inserted to / deleted from often. Over time they suffer from index bloating even though the autovacuum is configured and runs regularly. I'm ...
10
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2answers
711 views

Is there a MySQL performance benchmark to measure the impact of utf8_unicode_ci versus utf8_general_ci?

I read here and there that using the utf8_unicode_ci collation ensures a better treatment of unicode text (for example, it knowns how to expand characters such as 'œ' into 'oe' for searching and ...
4
votes
1answer
3k views

How to calculate max_connections for PostgreSQL and default_pool_size for pgbouncer?

Is there a rule or something I can use to calculate a good number for max_connections, default_pool_size and max_client_conn? The defaults are odd. PostgreSQL defaults to max_connections=100 while ...
3
votes
1answer
4k views

How can I tell if NUMA is enabled on a MongoDB server?

Our mongodb process is consistently using >100% of our CPU (this is on an Ubuntu 64-bit server on Linode) and we're casting about for performance improvements. One suggestion we found was that ...
1
vote
2answers
336 views

Low priority batch processes on live Mongo database

We want to run MapReduces on our live Mongo database, mainly so that we can extract metrics. However, we've had some bad outages caused by these MRs bogging down the Mongo server (in particular 100% ...
-1
votes
3answers
748 views

Redirect MySQL queries to another server [closed]

In order to lower system usage I'm planning to use another server to store my databases. so how can I redirect MySQL queries to another server or make MySQL to store databases on another server?
1
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4answers
4k views

How fill a database mysql with examples data?

i'm looking for a software that i can use to fill a mysql db (structure created by joomla, drupal or any CMS or script) with samples data for tot MB, so i can decide to put 400 MB of data in my tables ...
1
vote
1answer
60 views

Is there a “rigorous” method for choosing a database? [closed]

I'm not experienced with NoSQL, but one person on my team is calling for its use. I believe our data and its usage isn't optimal for a NoSQL implementation. However, my understanding is based off ...
0
votes
1answer
159 views

ft_stopword_file not picked up

I have a VPS server with a company called Webfusion. I want to remove some or all of the FULLTEXT stopwords because some specific words needs to be searchable with my DB content. I opened ...
1
vote
1answer
363 views

Is there a negative impact to using SQL Server with a lower compatibility level

We have SQL Server 2008 R2 which we are using for a database with a compatibility level set as 2005 (90). We will by upgrading it to 2008 at some point, but in the meantime I would like to know if ...
-1
votes
1answer
545 views

MySQL runs at >=100% CPU, heavy disk I/O?

Recently my Debian Linux server has been experiencing slow web server response times. I've investigated and it seems that MySQL is the culprit, yet there are no slow queries indicated by the slow ...
0
votes
1answer
116 views

Server Performance

I know very little about performance tuning of servers etc... so i thought i'd put this up here as i start some research on it, just to get some direction. I am in the process of migrating from my ...
0
votes
1answer
120 views

Why does MySQL use a different index for my query in different versions?

I have a large-ish InnoDB table (about 800MB), and I'd like to count rows. I know SELECT COUNT(*) has issues in InnoDB, but one of the solutions I've seen is to create a secondary index, which is ...
3
votes
1answer
543 views

Most efficient/quick SQL database update/restore method

I'm working on a very large database (250+ gigs) with well over 225 million records. The database is hard to work with simply from its sheer size. This database will only be used as read-only. We're ...
0
votes
2answers
171 views

Improving latency between developer machine and oracle db

It seems our developers are concerned with the latency they are getting between their dev machines at site a and the database which is at site b. Ofcourse the obvious thing is to have as little as ...
0
votes
1answer
86 views

Reccomendation for tuning 100's of SQL Databases

I'm running several SQL servers, each running a few hundred multi-gig databases for customers. They are all setup homogeneously as far as the schemas are concerned, however customer usages of the ...
1
vote
1answer
241 views

How does MySQL 5.5 and InnoDB on Linux use RAM?

Does MySQL 5.5 InnoDB keep indexes in memory and tables on disk? Does it ever do it's own in-memory caching of part or whole tables? Or does it completely rely on the OS page cache (I'm guessing that ...
1
vote
1answer
349 views

Database Server Hardware components (order of importance), CPU speed VS CPU cache vs RAM vs DISK

I am new to database world and would like to know what are crucial hardware specs when it comes to database performance. I have searched the internet and found this so far (In order of decreasing ...
2
votes
1answer
299 views

MySQL performance on FreeBSD after moving db files from /var

I was running out of space on /var so I moved my db dir to /usr and noticed a significate decrease in performance. In addition I noticed that performance is much slower as well under any Jailed ...
1
vote
1answer
249 views

MySQL: view read/write proportion, per specific table

I'm optimizing the configuration of a MySQL server, running only Bromine. This is non specific to application, and was just noted for completeness. I am trying to determine if switching from MyISAM to ...
2
votes
1answer
53 views

Consolidating SQL Server

We have a number of SQL Server 2008 R2 standard servers, each for a single application that we'd like to consolidate into one physical server. Running perfmon on these servers they're not using a ...
0
votes
2answers
184 views

Will a raid 10 help my db server in terms of trans/sec?

I've been reading about 10k drives being able to run 166 transactions per second vs 250/sec on 15k drives, which in both cases is just the number of rotations per second. What does this really mean ...