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36
votes
18answers
768 views

Poor internal database - replace it or chuck hardware at it?

So - we have an internal company database, the usual kind of stuff: manages clients, phone calls, sales deals and client agreements/schemes. It's an Access 2000 front-end, and an SQL Server 2000 ...
10
votes
5answers
6k views

SQL Server Express for Production Databases?

We are about to roll out a dual web/internal transactional application where each client has their own database. Each database is very small - under 50MB each, so we were wondering if it would make ...
10
votes
2answers
712 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 ...
9
votes
1answer
7k views

Do I need to REINDEX and VACUUM a table after deleting lots of rows?

I am running a PostgreSQL database that has several tables which store logging information. This information is for reporting purposes only and gets dumped to a file and deleted from the database if ...
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 ...
6
votes
1answer
2k views

Bad performance for a large join query in PostgreSQL 8.4.4, despite enough memory to cache entirely

Question How can I make the query described in this post faster, in particular by making PostgreSQL using the available RAM? - Note that I have tried to configure effective_cache_size and ...
5
votes
4answers
5k views

MySQL, disk I/O and SSD drives

We have a LAMP box with 2x mirrored 1 TB WD Black Caviar disks running the whole OS and MySQL. 8 GB / RAM, 2x quad core CPUs. We're really taxed on disk I/O, and I've been thinking of ...
5
votes
7answers
1k views

Optimizing performance across thousands of SQL Server databases

We are building an application where each client will have their own database. None of the databases are particularly large (20MB to 400MB each), but there will be ~5,000 to start and at any one time ...
5
votes
5answers
2k views

PostgreSQL High Performance Setup

I am setting up a server with the following specs: * Qty 4 Processors (AMD Opterons with 12 cores each) * 32 GB Memory * Qty 8 HDD (15K SAS Dual Port) * CentOS 5.5 * JBoss * PostgreSQL It is likely ...
4
votes
1answer
1k views

PostgreSQL - count() performance and how to tweak it?

I've done some reading in google and the only thing I did was get myself confused. Some of the people say that count() is slower with many records, others say you can cache the number or even use ...
4
votes
1answer
147 views

Are there any performance differences between Oracle Entreprise and Oracle Standard editions?

Someone has asserted to me that the reason why one database is performing better than another (50-100%) is because one has Enterprise Edition and the other has Standard Edition. Given the same ...
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 ...
4
votes
1answer
311 views

Mysql InnoDB table size performance

I have a table that is closely approaching 2 million records. This table stores a history of transactions. This is on a high traffic website but also the table is not accessed regularly. We ...
4
votes
1answer
618 views

Option shared_buffers in PostgreSQL

I have a server with 4GB of RAM and PostgreSQL 9.0.3 on Centos 5. I'm using pgbench and pgbench-tools to measure performance using two pgbench-tools queries: select and tpc-b. With default settings ...
3
votes
4answers
777 views

master-slave-slave replication: master will become bottleneck for writes

the mysql database has arround 2TB of data. i have a master-slave-slave replication running. the application that uses the database does read (SELECT) queries just on one of the 2 slaves and write ...
3
votes
2answers
1k views

extreme slowness with a remote database in Drupal

We're attempting to scale our Drupal installations up and have decided on some dedicated MySQL boxes. Unfortunately, we're running into extreme slowness when we attempt to use the remote DB - page ...
3
votes
9answers
723 views

Can you break down relative MySQL load by “source” of query?

I am trying to improve server performance, and it is clear that MySQL is a major contributor to the problem. Troubleshooting it, however, is very hard. I am using the slow query log to target ...
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 ...
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 ...
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 ...
3
votes
2answers
326 views

Very large database, very small portion most being retrieved in real time

I have an interesting database problem. I have a DB that is 150GB in size. My memory buffer is 8GB. Most of my data is rarely being retrieved, or mainly being retrieved by backend processes. I would ...
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 ...
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 ...
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 ...
2
votes
3answers
4k views

Which is faster? 4x10k SAS Drives in RAID 10 or 3x15k SAS Drives in RAID 5?

I am reviewing quote for a server upgrade. (RHEL). The server will have both Apache and MySQL on it, but the reason for upgrade is to increase DB performance. CPU has been upgraded massively, but I ...
2
votes
2answers
4k views

How well does PostgreSQL perform with a large number of databases?

We have an web application whose architecture requires that any registered user (a company, actually) should be isolated from the other, i.e., I'll run the same webapp with the same data models, but ...
2
votes
3answers
1k views

Do InnoDB or MyISAM tables offer better insert performance in MySQL 5.1?

I need to insert rows as fast as possible into a database with freshly created tables and no indexes. I'm looking at on the order of 20M rows, which is not that much. Would InnoDB or MyISAM tables ...
2
votes
3answers
2k views

PostgreSQL 9.0.X or 8.4.X - performance, replication, stability

I've been developing an app w/ server infrastructure for a while now, and I'm getting ready to release soon(ish). So far the server backend has been running on PostgreSQL 8.4.7, and it's working as ...
2
votes
3answers
173 views

What would be better solution a single database or multiple databases, one for each customer

I building a software that is going to have a lot of users (hopefully) I will have users that dont have much records or exceed normal data and I would also have the big users which will have millions ...
2
votes
3answers
3k views

Need help with Access Database with Front End and Back End really slow with more than 1 user

We have had a consultant install a database for a client that is based on Access 2007 with a front end (on each workstation) and I guess the database back end (on the file server, it is a server 2003 ...
2
votes
3answers
1k views

mysql performance tuning, write, get db into ram

I am trying to improve the performance of a website by optimizing the Mysql server. In addition to general optimization I have a feeling that some write operations take an unacceptably long time. The ...
2
votes
3answers
1k views

How can I speed up SQL Server queries on Amazon EC2?

Our SQL queries sometimes take too long. We have a Windows Server 2003/SQL Server 2005 setup. We have already created indexes everywhere that's possible. Can we get quicker disks? Any ideas from ...
2
votes
3answers
374 views

PostgreSQL lots of writes

I am using postgreSQL for a scientific application (unsupervised clustering). The python program is multi-threaded so that each thread manages its own postmaster process (one per core). Hence, their ...
2
votes
1answer
300 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 ...
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 ...
2
votes
2answers
77 views

Multiple SQL Server unique indexes with different includes

In SQL Server, suppose I have a very large table (columns A through Z) which has a CLUSTERED PRIMARY KEY on A and a UNIQUE NONCLUSTERED index IX1 over columns B,C,D include E,F,G. I then need to cover ...
2
votes
3answers
3k views

MySQL maintenance - how to clear the buffer?

We have a server running our web app (PHP / MySQL) which is SLOW. My predecessor says that: "We use to do database maintenance, which use to clear the buffer, cached and unwanted variables." And I ...
2
votes
2answers
2k views

Maximum number of database inserts per second

I am looking at designing a system that will be recieving very many records. Is there any fixed limit on how many inserts you can do in a database per second? We normally use MS SQL server, is ...
2
votes
1answer
90 views

How can I tell how my oracle databases configurations' differ?

I have two databases with the same data, running on the same physical server. They are performing differently (one is twice as fast as the other). I've compared the Initialization Parameters and ...
2
votes
1answer
308 views

SQL Server 2000 HIGH CPU Usage with BusinessObjects reports (unsolvable?)

I have one of those weird questions, those ones that are nearly unsolvable (the only way to really solve them is to throw out the technology and buy new ones). I've had a number of experts (about 10 ...
2
votes
1answer
487 views

Tools for planning a SQL Database size requirement

I'm about ready to start setting up a SQL data warehouse for some SQL Server Analysis Services. The data that I am going to slice and dice lives in an off site database that I don't control, so my ...
2
votes
1answer
1k views

Loading large CSV into Postgres

I'm trying to load a CSV of about 100M records (around 8GB on disk) into Postgres via the copy command: copy mytable from 'path/to/myfile.csv' with CSV; I have been monitoring the progress by checking ...
2
votes
2answers
1k views

SQL Server 2005 standard filegroups / files for performance on SAN

I submitted this to stack overflow (here) but realised it should really be on serverfault. so apologies for the incorrect and duplicate posting: Ok so I've just been on a SQL Server course and we ...
2
votes
0answers
64 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
189 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
3answers
194 views

Roughly how much use could you expect to squeeze out of a ~$1000 MySQL server?

I know this is a horrible, generalized question with no good answer, and I apologize ahead of time, but I wonder if someone could take a stab at a very broad estimate. Let's say you have a dedicated ...
1
vote
2answers
44 views

Store TIME in SQL

What is the correct way to store the TIME of day in SQL? Have a field that cares only when an action took place. Example values will be 2:30 PM or 14:30, it doesn't matter to me which. This ...
1
vote
2answers
156 views

What kind of database server should I use for a 500k stored procedure calls per day database?

I have a database that gets about 500,000 stored procedure calls a day in addition to other stuff. It's running too slow for us and we're going to upgrade it when we get around to it. I'm looking at ...
1
vote
3answers
590 views

MySQL becomes unresponsive a few times per hour

I'm stuck trying to solve a MySQL issue. A few times an hour, for about 60s, MyuSQL becomes unresponsive, causing our site to be inaccessible during that period. I enabled the slow query log and found ...
1
vote
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. ...