Trash Compactor
April 12, 2018
We recently found a huge leak in the UE4 garbage collector, particularly rearing its head on dedicated servers for large open-world games. Servers for arena type games with short play times (<1 hour) seem to be little affected, and clients don’t see the problem much either. “Huge” is not hyperbole here – we’re talking the garbage collector alone using up to 10 GB of ram in under 24 hours of server operation!
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Placating The Natives
January 8, 2018
In this article we delve into Blueprint Nativization, a relatively new feature of UE4 that offers significant performance improvements for many projects. Sadly, it often doesn't work out of the box - we've spent some time fixing and improving it for a particular project that we were working on. We have a LOT of changes to present here - some of which have already been implemented into UE4.
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PhysX: The Case Of The Leaky Cloth
August 28, 2017
We found quite a large leak within Apex 3.4 (currently used in Unreal Engine 4, amongst others) - in a relatively short run of the title that we were working on, we saw over 150mb of leaked memory. Here, we present some changes that will fix this
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It’s A Size, Jim, But Not As We Know It, Not As We Know It…
February 24, 2017
A really small bug fix is presented here - with a lot of Trekkie banter to fluff the piece out... and why not?
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Sign Of The Times
February 23, 2017
PVS-Studio pointed us toward some code with suspiciously mixed signed/unsigned math. This was actually causing some issues - and here we tell you how to fix them
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Clear And Reset Danger
February 23, 2017
A common programming mistake is fixed here, this time in the FBX importer
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The Sadness of the Ignored Null Pointer
July 14, 2016
In this post we present an optimization coming from removing some pointless null pointer checks. The way that we found this was quite interesting
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The Battle of the Lean and the Inlined Bone Functions
July 12, 2016
We took a look at the inlining of a certain part of the codebase and were shocked with what we found... we then went about improving it
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ToString() Or Not ToString()… Wait, What’s The Question?
July 6, 2016
ToString() is one of the most commonly called functions in UE4 - certainly across the editor, the content cooker and such. Here we take a look at it and make it over twice as fast
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Tiny Code Fixes – Part 1
July 4, 2016
Here we present several small code fixes and improvements in a nice little package
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Package Versioning… How It Works… And An Optimization
June 29, 2016
UE4's Package Versioning is a bit of a dark art for most.. here we try to remove some of the confusion around it - while, again, offering some improvements through optimization
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Portrait Of A Serialize Perf Killer
June 21, 2016
With performance critical editor and cooker code, it's well advised to consider performance when adding tests for rare errors. Here we take a look at this and show by, by considering the CPU pipeline and code cache, a simple change can yield a significant performance improvement without reducing stability
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Sweeping Up And Disassembling A Physics Macro
June 20, 2016
Macros can often be useful to make certain programming tasks simpler - but they can also cause hidden performance headaches that might otherwise be avoided. Here we look at one of those - and how to improve it
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When Are Shopping Lists A Waste of Time?
June 3, 2016
We take a look at some list generating code with UE4 - and why it was completely pointless
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Using The Disassembler To Highlight Optimization Targets
May 23, 2016
We use the debugger's disassembly view to look at FPaths::IsRelative() after it shows up in our profiling tests. Then we optimize it
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Static Code Analysis With PVS-Studio (Part 3)
May 16, 2016
The third part in our series looking at coding errors found by using the static code analysis tool PVS-Studio
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The Cook, The Resave, His Garbage And Her Optimization
May 4, 2016
We present here a way to improve cook times by reducing the frequency of garbage collection
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The Case Of The ExportHash String Monster
April 29, 2016
We found CreateExportHash() was showing up in profiling the cooker - so we optimized it. Our findings and changes are presented here
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Static Code Analysis With PVS-Studio (Part 2)
April 27, 2016
The second part in our series looking at coding errors found by using the static code analysis tool PVS-Studio
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Patch Content Early – NOT At Runtime
April 25, 2016
We present an optimization that removes a significant amount of memory churn from the animation code
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Static Code Analysis With PVS-Studio (Part 1)
April 19, 2016
The first part in our series looking at coding errors found by using the static code analysis tool PVS-Studio
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A Huge PhysX Memory Churn Reduction
April 18, 2016
Here we implement a scratch buffer to reduce temporary memory churn passing through PhysX
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The Smallest, Coolest Optimization
April 17, 2016
While profiling a game's runtime, we found that 40% of memory allocations were coming from a single function. The fix/optimization involves adding a single character
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The Clue In The Code Comments
April 17, 2016
We present a tiny little fix for a simple - but serious - coding error in the UE4 codebase
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