Hans and Franz

As memory becomes cheaper, servers are delivered with larger memory configurations and applications are starting to address more of it. This is generally a good thing from a performance standpoint. However, this can create performance issues when you’re using the default memory page size of 4 KB on x86-based systems.

To address this, Linux has a feature called “hugepages” that allows applications (databases, JVMs, etc.) to allocate larger memory pages than the 4 KB default. Applications using hugepages can benefit from these larger page sizes because they have a greater chance of finding memory mapping info in cache and thereby avoid more expensive operations.

In order to understand the benefits of hugepages, it helps to know a bit more about memory mapping, page tables and the TLB (translation lookaside buffer).

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