ZRAM Will See Greater Performance On Linux 5.1 - It Changed Its Default Compressor

Written by Michael Larabel in Linux Kernel on 15 March 2019 at 12:09 AM EDT. 34 Comments
For those relying upon ZRAM to provide a compressed block device in RAM for cases like using it for SWAP or /tmp, with Linux 5.1 you might find it performing better than earlier kernels.

With Linux 5.1, the ZRAM block driver has changed its default compressor from "lzo" to "lzo-rle."

LZO-RLE? This LZO-RLE support came via Arm developers for enhancing the LZO compression support. LZO-RLE was added just last week to the Linux kernel at the start of the 5.1 merge window. LZO-RLE is short for "Run-length Encoding" and is designed to offer better performance over traditional LZO. Arm developers are also the one applying this default compressor change.

With the change to the ZRAM driver, the LZO-RLE mode is said to yield similar compression ratios to traditional LZO but with higher performance.

In a previous mailing list thread by Arm's Dave Rodgman, he found when opening 80 browser tabs to cause swapping on the system that there was a 27% reduction in total time spent compressing/decompressing data. Hopefully you don't suffer from heavy swapping in the first place, but if you do or you rely on ZRAM for /tmp or similar use-cases, with Linux 5.1 you will hopefully see better performance.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week