TeamCity Hub plugin

Greetings, everyone!

Today we are releasing the first version of the plugin for TeamCity which provides integration with JetBrains Hub, a single point of entry for user management across all JetBrains team tools.

The first version of the Hub plugin for TeamCity handles authentication via Hub and user details synchronization; so if you are already using Hub, install our plugin to enable single sign-on (SSO) and to automatically update user details from Hub in TeamCity.

The current plugin version is compatible with TeamCity 9.1.x and Hub 1.0.

Download from here and install it on your TeamCity server as usual. After the server restart, the integration can be managed using the Administration | Hub Settings page.

Please refer to the documentation for the usage details.

We keep working on the TeamCity-Hub integration, and your feedback is greatly appreciated!

Happy connecting and building!

Posted in Features, How-To's, News & Events, Tips&Tricks, Uncategorized | 3 Comments

Make profiling a part of continuous integration (.NET)

If you’re a .NET developer who doesn’t follow our ReSharper Ultimate blog, then you probably missed a couple of blog posts about two new cool features in our dotTrace and dotMemory .NET profilers. Why are we writing about them in the TeamCity blog? Because these features are closely related with TeamCity and CI in general: they allow you to make performance and memory profiling a part of your continuous integration builds. So what is this hype all about?

Performance profiling in CI

Let’s begin with dotTrace and performance profiling. Along with dotTrace 6.2, we released a dotTrace Plugin to TeamCity. It allows you to prevent application performance regression by profiling your integration tests. The workflow is pretty simple:

  1. Write an integration test that runs some performance-critical functionality in your application.
  2. In the plugin, set a performance threshold for this test, which is the execution time value in ms or value taken from previous successful builds.
    Now, if the test exceeds its threshold, the plugin will fail the build and save the collected performance snapshot to build artifacts.
  3. Open the snapshot in dotTrace and find the exact cause of the performance issue.

dotTrace Plugin Build Overview

dotTrace Plugin Build Log

More details on the plugin are available in this post.

Memory profiling in CI

Not so long time ago we released dotMemory Unit – an additional unit testing framework that allows you to write tests that check your code for all kinds of memory issues, including memory leaks, high memory traffic, etc. For example, here’s how easy it is to check memory for objects of some Foo type with an NUnit test:

Now the time has come for the dotMemory Unit standalone launcher that can be used in CI. For TeamCity users, we have something even better: a dotMemory Unit plugin. This plugin adds the support for dotMemory Unit to all TeamCity .NET test runner types. This means you can run tests that use dotMemory Unit along with other tests on your CI server.

dotMemory Unit Failed Test

For more information on the dotMemory Unit plugin, please see this blog post.

You’re welcome to give the plugins a try! Note that they are absolutely free, so this won’t cost you anything.

Posted in Features | Tagged , , | 3 Comments

TeamCity Digest

As software builders, we always want to be on top of things, so we monitor the environment for anything new that comes up in the world of continuous integration and continuous delivery. Every now and then we stumble upon articles, blog posts, and tweets about various ways of TeamCity usage, new integrations, plugins, or just news that is relevant.

Here is the list of publications that have recently caught our eye. We found them useful, and we hope you will as well. now provides a community build server based on TeamCity: They’ve recently held a webinar about it, which you can watch in recording: Discovering TeamCity and Build PowerShell org.

This article covers some steps for those who are doing continuous integration on a Xamarin app: What to consider when doing Continuous Integration on a Xamarin app.

There is a new integration for TeamCity and DataDog, a cloud-scale monitoring tool: Track performance impact of code changes with TeamCity and Datadog

Good news for the PHP community using TeamCity:

While there is no out-of-the-box support for Docker in TeamCity, this article explains how the two can be used together with the help of an external plugin: CI with Docker and TeamCity.

This one guides you through preparing your build server to build VS 2015 projects: Getting Your Build Server Ready for VS 2015.

And here the author focuses on xUnit and dotCover meta-runner: Showing the love for and dotCover in Teamcity.

These are just a few links that have come to our attention recently. We are sure there are many more blog posts, news, tutorials, and other materials around, which could be useful for TeamCity users like you.

If you are interested in reading more of such digests, please let us know in the comments. And feel free to share such content with us via twitter @teamcity.

Check all the TeamCity Digests.

Posted in Blogroll, Digest, FYI | 1 Comment

TeamCity 9.1.3 hotfix is available

Hello, everyone!

We’ve decided to publish 9.1.3 bugfix release with a fix for critical regression which has been reported to us recently:

  • TW-42498 – As of 9.1.2 having a hashbang in a Command Runner script no longer works.

If you already downloaded 9.1.2 and planned upgrade during this weekend, please download 9.1.3 instead.

Release notes
Download page

Sorry for inconvenience and happy building!

Posted in Uncategorized | Comments Off on TeamCity 9.1.3 hotfix is available

TeamCity 9.1.2 is here


Greetings, everyone!

Today we’re announcing the arrival of TeamCity 9.1.2, a bugfix to the latest TeamCity version.

Build 37168 addresses over 100 problems, and we are thankful to our careful users for reporting issues and helping us make TeamCity better.

The problem with updating Subversion VCS roots containing parameters, which surfaced after upgrade to TeamCity 9.1.1, has been resolved. There are also several important security-related fixes.

This version also includes updates to the bundled tools, and now TeamCity comes with:
– ReSharper command line tools 9.2
– Visual Studio Addin Web installer from R# Ultimate 9.2 release
– dotCover 3.2.

See the full list of fixed issues in our release notes, download the new build and don’t hesitate to upgrade: this release does not change the data structure, so you can roll back to one of the 9.1. versions easily if required.

Oh, and by the way now TeamCity features new build status icons (.png and .svg) available via a REST API request:

statusIcon (1)



May you have successful builds only and Happy building!

Posted in Bugfix, EAP, Features, FYI, News & Events, Uncategorized | Comments Off on TeamCity 9.1.2 is here

TeamCity at SQL in the City 2015

Meet the TeamCity team at the SQL in the City conference in Seattle this upcoming October.


TeamCity will be part of Redgate’s SQL in the City event this October. SQL in the City takes place in London on Friday 16 October and in Seattle on Monday 26 October, welcoming hundreds of professionals who work with SQL Server.

Besides the opportunity to take part in multiple sessions covering best practices for SQL Server development, administration, and Database Lifecycle Management (DLM), participants will have a chance to receive a demo of TeamCity and meet TeamCity team representatives at the JetBrains booth.

See you in Seattle and happy building!

Posted in Blogroll, News & Events, Partner | Comments Off on TeamCity at SQL in the City 2015

Benchmarking TeamCity

How many agents can be handled by TeamCity server?

This is our official reply to the question in the title:
The latest TeamCity version is known to work well with up to 300 build agents (300 concurrently running builds actively logging build run-time data). In synthetic tests the server was functioning OK with as many as 500 agents (the server with 8 cores, 32Gb of total memory running under Linux, and MySQL server running on a separate comparable machine).

This reply is based partly on our own experience and partly on our internal benchmarks. In this post I’ll explain what kind of benchmarks we use and will also show some of the results measured against the latest TeamCity version – 9.1.1.

We’ll start with the TeamCity architecture first: this will let us understand results better.

As you already know, TeamCity consists of a server and a number of agents. Agents run builds and send results (build log, artifacts, tests, etc.) back to the server. Most of the time the results are being sent in real time, while build is still running, which allows us to show a nice real-time progress of the build in the web interface, send notifications early, and so on.

An agent sends results to the server by the RPC protocol established over HTTP. During processing of these results, the server stores data in the build log on the file system and can also write some data into the database. For instance, all statistic values, as well as the information about tests (name, duration, status) are stored in the database.

Both the agent and the server maintain buffers for the build results data: the agent sends results to the server when the buffer becomes full, the server also processes results in packs, because it greatly improves performance. To reduce concurrency costs on the server side and in the database, all build results on the server side are processed by N worker threads, where N roughly equals to the number of cores. So even if we have 300 agents sending results at the same time, they will be processed on the server with the concurrency not greater than the number of cores.

So what happens if the server cannot sustain the load? All running builds have bounded message queues, so if these queues become full because workers cannot keep up with the data from agents, agents will get blocked on an attempt to add new data from builds. As a result, the build time will start increasing. When this happens, we can observe that the build script itself has already finished on the agent, but the server still did not mark the build as finished because it is still processing the build results.

This brings us to a simple idea of the benchmark: we need to generate build logs from a lot of agents for some time with a constant rate; then we need to stop the load generator and measure the amount of build logs processed on the server up to this time. Once we know the duration of the benchmark and the rate of build log generation, we can estimate the amount of build logs which should’ve been processed. Having this delta (estimated amount – actual amount) we can judge whether the server is ok with the load or not.

Meet Benchmark plugin

This benchmark idea has been implemented as a TeamCity plugin. The plugin adds additional tab under the Administration -> Diagnostics page. On this tab you can configure benchmark parameters, such as: the number of concurrently running builds, the duration of benchmark, the build log output rate and others.


Some of the fields require additional explanation:

  • Build log output rate – the number of log lines produced by a build per second
  • Percent of successful tests in build log – assuming that one line of the build log represents a test, this is the percent of build log lines to allocate for tests reporting. So if the build log output rate is set to 30 lines per second, and the percent of successful tests is set to 50, then the load generator will produce 15 tests per second and 15 other random log lines for each build.
  • Percent of failed tests in build log – the meaning is the same as with the successful tests percent; note that the sum of and cannot exceed 100.

Note that the build log output rate and percent of successful and failed tests can be pre-calculated based on builds history of projects already configured on the TeamCity server (see “Pre-load parameters” button).

The benchmark workflow is pretty simple. When the benchmark starts, it:

  • creates a dedicated agents pool named Benchmark with the number of agents equal to the number of configured concurrently running builds
  • creates a project with build configurations where builds will start: one configuration for each build
  • adds all builds to the queue and waits till builds start
  • spawns the load generator as a separate java process and waits till it finishes
  • cleans up the data: stops builds, removes the project and build configurations, removes the agents and the agent pool; cleanup is also performed if the benchmark is interrupted using the Stop button.

The log file for each benchmark is stored in a separate file under the <TeamCity logs directory>/benchmark folder. If additional comments are specified, they will be stored in the benchmark log as well.

Benchmark results

So we’ve done some measurements on our own hardware:
TeamCity server:

  • CPU: Core i7-4790, 3.6GHz
  • RAM: 32Gb
  • SSD: Intel 530, 240Gb
  • HDD: Seagate Barracuda ES (ST3500320NS), 7200RPM

Database server:

  • CPU: Core i7-4790, 3.6GHz
  • RAM: 32Gb
  • SSD: Intel 530, 240Gb
  • HDD1: Western Digital Velociraptor (WD3000HLFS), 10000RPM
  • HDD2: Western Digital Caviar Blue (WD6400AAKS), 7200RPM

Ubuntu 14.0.4 was installed on both servers. In case of the TeamCity server, the TeamCity data directory was placed on an HDD. On the database server, the data files and transaction logs were placed on an SSD. In all of the cases the Ext4 file system was used.

Percona server 5.6.25 was installed on the database server machine. We’ve selected Percona because it is well known for it’s performance optimizations compared to regular MySQL. The following parameters were changed in my.cnf file:

thread_handling=pool-of-threads # Percona and MariaDB only

TeamCity server was started under Java 1.8.0_45 with Xmx set to 3Gb.

To make the benchmark results more realistic, we set up a few open source projects and measured their build log output rate using the “Pre-load parameters” feature. See the results below:

Project name Build log output rate per build Percent of build log used by successful tests Resulting tests rate per build
commons-math 71 lines/sec 80% 57 tests/sec
JUnit 46 lines/sec 61% 28 tests/sec
Maven 45 lines/sec 28% 12.6 tests/sec
Spring Framework 20 lines/sec 50% 10 tests/sec
Netty 30 lines/sec 21% 6.3 tests/sec
Hibernate ORM 60 lines/sec 5% 3 tests/sec

Let’s see how these numbers are calculated:

  • build log output rate = <total number of log lines> / <build duration>
  • tests rate – assuming that each test is represented in the build log by at least one line:
    tests rate = <build log output rate> * <number of tests> / <total number of log lines>

As you can see, these formulas do not take the test duration into account. So even if there are lots of fast tests with the duration of 1ms, but besides running tests a build also performs other time consuming tasks, the resulting tests rate will be far from 1000 per second. This is especially true when many builds are running concurrently on the real server. In this case the builds will be in different states: some can run tests, others download artifacts, compile code, etc, etc. So we can safely say that it is unlikely that there will be a situation when all of them report tests with the rate of 1000 per second at the same time. As a result, the real load which can be sustained by the server is much bigger than one would expect by simply looking at the duration of individual tests.

Final results

For each of these projects we measured the maximum number of concurrently running builds our system can sustain without significant increase of the build duration (10% increase in build duration was considered acceptable). See the results below:

Project name Max number of concurrently running builds CPU usage (server/database)
commons-math 320 42% / 20%
JUnit 570 40% / 18%
Maven 990 50% / 15%
Spring Framework 1300 52% / 15%
Netty 1600 58% / 10%
Hibernate ORM 1650 60% / 9%

Some observations:

  • even with this hardware which is not quite optimal for the server tasks, some very promising results can be achieved
  • the more tests produced by the build per second, the smaller the resulting number of agents concurrently running builds; in our case commons-math has rate of 57 tests per second which may not sound like a lot, but surprisingly the majority of projects have much lower rate of tests. In general, the bigger the project, the slower its tests, which is understandable, as besides tests, build scripts also perform lots of other time-consuming tasks
  • the bigger the rate of the build log output, the bigger the load produced on the TeamCity server machine; with the large number of agents, the CPU usage on the TeamCity server machine reached 60%; obviously, it is not a good idea to dedicate 60% of CPU just to process data from agents as there are other CPU intensive tasks which should be done by TeamCity server
  • the load generator worked as a separate java process, and at peak times it took some CPU as well, although this time was negligible comparing to the CPU time used by the server
  • the CPU usage on the database server only reached 20% which probably can be explained by a very simple workload imposed by our test – mostly inserts, no complex queries at all

Note that the results of this benchmark cannot be applied blindly simply because this benchmark is a synthetic test and, like many other synthetic tests, it does not entirely represent the real life. For now it only measures one aspect of the server performance. It does not cover things like artifacts downloading and publishing, user requests, VCS operations, etc, etc.

On the other hand, if you plan to move your server to new hardware, this benchmark can help you to tune the hardware, disks and database parameters to achieve better performance.

How to run benchmark on your own server

The Benchmark plugin is available for download.

The plugin is compatible with TeamCity 9.1.x.

If you want to try this plugin on your hardware, please read our suggestions below.

The plugin creates agents and each agent needs to be authorized, which means you should have enough agents licenses to run benchmarks. Besides, using this plugin on the production server may be a tempting idea, but the plugin can impose a significant load on the system, making it hard to use by other users. Moreover, in case of bugs in the plugin or server crashes, you can end up with lots of data which was not properly cleaned up – agents pool, agents, projects, etc. Finally, it may not be easy to fine tune the production system for better results as it requires downtime.

Because of that we recommend to setup a separate server, obtain an evaluation license from our site to be able to run the server with unlimited agents, and then run benchmarks on this system. Note that using the latest TeamCity version is also recommended as it may have significant performance improvements comparing to the version you’re using now.

Take a look at our documentation if you’re going to use MySQL or PostgreSQL database.

We would not recommend using HSQLDB for this benchmark: since we don’t recommend this database for production use, benchmarking against it is pointless. It’s a good database engine, but it is not as reliable and scalable as “big” databases. Big databases implement sophisticated approaches to keep your data safe (see for example: or HSQLDB being a database written in Java does not have a chance to implement similar reliability as it does not have proper access to hardware.

While running benchmarks, make sure to run them a few times, or at least run them with the duration not less than 180 seconds as this makes results more predictable. It is also recommended to perform a few warm up benchmarks after the server startup. Finally, if you choose to tune some parameters in the database or elsewhere, make sure to change one parameter at a time. Otherwise you may fail to notice which parameters give you better results.
Benchmarking is fun, but be prepared to spend tons of time on it!

We hope that you will use this plugin to assess your server performance, so if you do decide to run this benchmark, we will be really interested in seeing your results.

Happy benchmarking and building!

Posted in Design decisions, Features, FYI, How-To's, News & Events, Uncategorized | Comments Off on Benchmarking TeamCity

TeamCity 9.1.1 to the rescue!

Greetings, everyone!

Since TeamCity 9.1 was released, several issues requiring a quick fix on our side have been reported to our tracker.
The most noticeable of them are:
– problems with building .NET 4.6 projects and proper detection of .NET 4.6 on agents
– problems with running NUnit tests on Linux
– Swabra exclude rules stopped working in some cases
– problems with the TeamCity server launch on some platforms

In 9.1.1 all these problems are fixed.

We also added one feature to Amazon EC2 integration which had already been cooked for quite some time:
TW-34196 – ability to set IAM role on a running instance

Overall TeamCity 9.1.1 addresses more than 60 different problems. See the complete list of fixed issues in our release notes.

If you’re already using TeamCity 9.1, make sure to install this update. If you have not upgraded yet, please consider doing so, as all the new fixes are to be applied to the 9.1.x branch; no updates for TeamCity 9.0.x are planned.

Download and install TeamCity 9.1.1! As with any other TeamCity bugfix update, this version does not introduce changes in data format and can be easily reverted to TeamCity 9.1.

Happy building!

Posted in Bugfix, EAP, Features, Uncategorized | 2 Comments

TeamCity 9.1 release: truly historical and very personal builds

Greetings everyone!

So here it comes – after half a year and over 500 fixes since version 9.0 was released, despite being a minor version, TeamCity 9.1 brings you major improvements!

The new build is coming out with significantly enhanced capabilities to store the project settings in the VCS: now the settings in your build can be different from those currently on the TeamCity server, which means that you can:

  • run true historical builds: use a particular revision of the source code and run a build with the corresponding project settings
  • store different settings in different branches, and run a build in a particular branch with the settings from this branch
  • change project settings in your IDE, and run a personal build/pre-tested commit with these custom settings.

Good news for .Net developers – this release brings enhanced .NET tools support:

  • anticipating the upcoming release of Visual Studio 2015, TeamCity already supports the latest versions of the tools in the Visual Studio 2015 lineup
  • Windows PowerShell 5.0 is also supported
  • the new Visual Studio Tests runner integrates the MSTest and VSTest runners
  • Mutual support between TeamCity and NUnit 3.0 guarantees compatibility of NUnit and TeamCity future releases.

As with every release, we were busy with UI improvements, and one of the most noticeable is probably ANSI-coloring support in our build log, which presents endless possibilities for those with artistic aptitude: buildLogArty

For the full list of new features and fixes see our What’s New on the product web site and our documentation.

Download and install TeamCity 9.1 now!

Happy building!

Posted in Bugfix, EAP, Features, FYI, News & Events | 6 Comments

TeamCity 9.1 RC is out today

Greetings, everyone!

We are happy to announce the TeamCity 9.1 release candidate! We’ve been putting a concentrated effort into finalizing the new features and fixing issues, so here is our latest news.

Now unidirectional communication between the TeamCity agents and the server is enabled by default. Should you run into any issues, please let us know.

Besides, TeamCity 9.1 RC introduces a number of fixes in the Nunit 3.0 support. We’ve looked at the statistics related to the usage of code coverage tools with NUnit and decided that JetBrains dotCover will be the only coverage tool for NUnit 3.0 for now.

Other improvements include the bundled SBT plugin. See the full list of fixes in our Release Notes.

As usual, make sure to install this build in a test environment since it changes the data format, and downgrade is not supported.

Download TeamCity 9.1 RC build 36932 and let us know what you think in our forum or issue tracker!

TeamCity 9.1 will be out in a few days, so stay tuned!

Happy building!

Posted in Bugfix, EAP, Features, FYI, News & Events | Comments Off on TeamCity 9.1 RC is out today