Questions tagged [capacity-planning]

Capacity planning is the science and art of estimating the space, computer hardware, software and connection infrastructure resources that will be needed over some future period of time.

As per techtarget definition:

Capacity planning is the science and art of estimating the space, computer hardware, software and connection infrastructure resources that will be needed over some future period of time.

A typical capacity concern of many enterprises is whether resources will be in place to handle an increasing number of requests as the number of users or interactions increase.

The aim of the capacity planner is to plan so well that new capacity is added just in time to meet the anticipated need but not so early that resources go unused for a long period. The successful capacity planner is one that makes the trade-offs between the present and the future that overall prove to be the most cost-efficient.

Basic steps of capacity planning:

  1. Determine Service Level Requirements
    The first step in the capacity planning process is to categorize the work done by systems and to quantify users’ expectations for how that work gets done.
  2. Analyze Current Capacity
    Next, the current capacity of the system must be analyzed to determine how it is meeting the needs of the users.
  3. Planning for the future
    Finally, using forecasts of future business activity, future system requirements are determined. Implementing the required changes in system configuration will ensure that sufficient capacity will be available to maintain service levels, even as circumstances change in the future.

Capacity planning activities:

  • capacity analysis and prediction for storage, database, and application servers;
  • designing architectures to easily add and measure capacity.
  • handling sudden spikes.
  • predicting exponential and explosive growth.

Do not confuse performance with capacity: performance is based more on human work, and capacity is based more on computer resources.

85 questions
142
votes
3 answers

Can you help me with my capacity planning?

This is a canonical question about capacity planning Related: How do you do load testing and capacity planning for web sites? How do you do load testing and capacity planning for databases? I have a question regarding capacity planning. Can the…
voretaq7
  • 79,345
  • 17
  • 128
  • 213
125
votes
5 answers

How do you do load testing and capacity planning for web sites?

This is a canonical question about capacity planning for web sites. Related: Can you help me with my capacity planning? How do you do load testing and capacity planning for databases? What are some recommended tools and methods of capacity…
gWaldo
  • 11,887
  • 8
  • 41
  • 68
61
votes
8 answers

Does bigger capacity SSD have longer life due to wear leveling?

I have been told that you can get a longer lifespan of an SSD if you buy a bigger capacity SSD. The reasoning goes that newer SSDs have wear leveling and thus should sustain the same amount of writing whether you spread this writing on the (logical)…
Ole Tange
  • 2,836
  • 5
  • 29
  • 45
57
votes
2 answers

vSphere education - What are the downsides of configuring VMs with *too* much RAM?

VMware memory management seems to be a tricky balancing act. With cluster RAM, Resource Pools, VMware's management techniques (TPS, ballooning, host swapping), in-guest RAM utilization, swapping, reservations, shares and limits, there are a lot of…
ewwhite
  • 194,921
  • 91
  • 434
  • 799
36
votes
2 answers

How do you do load testing and capacity planning for databases?

This is a canonical question about capacity planning for databases. Related: Can you help me with my capacity planning? How do you do load testing and capacity planning for web sites? I'm looking to create a canonical question of tools and…
gWaldo
  • 11,887
  • 8
  • 41
  • 68
25
votes
9 answers

Maximum number of files in one ext3 directory while still getting acceptable performance?

I have an application writing to an ext3 directory which over time has grown to roughly three million files. Needless to say, reading the file listing of this directory is unbearably slow. I don't blame ext3. The proper solution would have been to…
knorv
  • 1,789
  • 6
  • 19
  • 29
13
votes
3 answers

MongoDB and datasets that don't fit in RAM no matter how hard you shove

This is very system dependent, but chances are near certain we'll scale past some arbitrary cliff and get into Real Trouble. I'm curious what kind of rules-of-thumb exist for a good RAM to Disk-space ratio. We're planning our next round of systems,…
sysadmin1138
  • 131,083
  • 18
  • 173
  • 296
12
votes
4 answers

How long does it take to fsck a volume?

We are running a website which is currently serving 3-5 million page views. Our site is a file sharing site and so it contains 250,000 files and few thousand symbolic links. The hard disk is a 1500GB SATA disk. Using hdparm we came to know that our…
khizar ansari
  • 205
  • 1
  • 2
  • 10
11
votes
1 answer

How to document a strategy for upgrading commercial software?

We haven't upgraded our RDBMS or server OS for nearly a decade. Another mission-critical software package is nearing two decades old and has been unsupported by its vendor for much of that time. Some among our management seem to think that this is a…
Fing Lixon
  • 211
  • 1
  • 5
11
votes
6 answers

Accurately trending random I/O performance for capacity planning

Where I work we have a numerous "big iron" servers which are used used for hosting many virtual machines using a Xen Hypervisor. These are typically configured with 32GB RAM, Dual Quad core processes and fast disks with gobs of I/O capacity. We're…
10
votes
2 answers

How do you estimate how much memory to buy?

I have a custom server application that runs on Windows 2008 R2. It is a home grown Windows Service written in .Net supporting a number of custom terminals. I have a test machine that has a similar specification to the live server and I have a set…
7
votes
4 answers

Open source DCIM stack?

Our 500-server data center is growing quickly and my manager has started investigating using a specialized Data Center Infrastructure Management (DCIM) package to help manage constraints. DCIM software aims to do everything: capacity planning,…
7
votes
3 answers

When using thin-provisioning with ZFS, how do you make sure you don't run out of physical disk space?

Forgive me if this seems like a fundamental question, but I couldn't really find anything concrete on Google, and I'm not a system administrator by trade. We are setting up a SAN at our office using NexentaStor with an 8-disk RAID Z3 configuration…
Mike Spross
  • 465
  • 1
  • 5
  • 13
6
votes
2 answers

Can I put the MySQL binlogs on a slow disk?

We have only 450 GB nvme space on our master server and the binlogs are using a lot of space, even if they are kept for only two days. Does writing the MySQL binlogs to a slower disk (like a remote directory) slow down the MySQL performance?
the_nuts
  • 412
  • 6
  • 18
6
votes
7 answers

When to Add another server(s)

When is the right time to start adding(or thinking about adding) servers to your Web Application? What are the difficulties involved in going from a single server(DB and Web) to multiple? For example: Most of the time you start with one sever that…
cgreeno
  • 203
  • 2
  • 10
1
2 3 4 5 6