Facebook Inc. is donating another of its internally developed tools to the open-source software community.

The social media giant said it’s adding the F14 hash table, which it uses to manage vast amounts of data, to Folly, its open-source library of software components written in the C++ programming language.

In a blog post, Facebook software engineers Xiao Shi and Nathan Bronson said hash tables are a mechanism used by software to store and search for data rapidly. They’re especially prized by developers for their ability to look up data quickly, even if the amount of data stored is increasing exponentially.

“Folly’s F14 is widely used inside Facebook,” Shi and Bronson said. “[It] is a good default choice – it delivers CPU and RAM efficiency that is robust across a wide variety of use cases.”

The engineers said hash tables are being more widely used these days as companies store increasing amounts of data, and they can have a significant impact on the capabilities of various software and applications. “They are such a ubiquitous tool in computer science that even incremental improvements can have a large impact,” Shi and Bronson wrote.

The engineers said one of F14’s biggest advantages over other hash tables is its ability to reduce the likelihood of collisions, wherein multiple keys in the hash table attempt to resolve the same queries. This can slow things down as it requires greater memory access, they explained.

F14 also helps reduce memory and central processing unit overheads, thereby improving software performance by allowing more data to fit inside the memory cache. It does that by using a hybrid storage mechanism called F14Fast, which works out the most efficient data storage method for each piece of information, according to its value type. It’s written using significantly less code than other hash tables, which also helps to boost performance, the engineers said.

Analyst Holger Mueller of Constellation Research Inc. welcomed Facebook’s initiative to open source F14, noting that hash tables are a basic construct used in many next-generation applications today. But he said they’re also very difficult to design and maintain, so developers should appreciate getting their hands on F14.

“With Facebook using F14 extensively, developers as well as CxOs can be reassured they’ll sit on not just functional but also efficiently-working code,” Mueller said. “The other open source benefit, of having more eyes on the code, is probably not really necessary given the industry strength scale of F14, but it never hurts.”

Facebook has made F14 available to download via GitHub.

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