Summer OSPP 2022:Support Multi Gen LRU in openEuler · Pull Request !167 · openEuler/kernel

Multi Gen LRU is a feature for optimizing the memory recycling strategy. According to Google's test, with the help of MGLRU, the CPU utilization of kswapd is reduced by 40%, the background miskill is reduced by 85% when 75% of the memory is occupied, and the rendering delay is reduced by 18% when 50% of the memory is occupied. This feature has been integrated into the Linux next branch. In this PR, the patch is integrated into the openEuler-22.09 branch.

MGLRU is mainly designed for memory recycling. First, the LRU linked list of the management page is divided into more algebra. In each generation, the number of page refluts is divided into different levels to achieve more granular management of the page. At the same time, when executing the kswapd daemon, scan the PTE of the active processes since the last execution, instead of directly scanning the physical memory. This can effectively use the spatial locality, improve the scanning efficiency, and reduce the CPU overhead.

In the current test results, the IOPS and BW indicators of the fio tool are significantly improved compared with the conventional recovery methods, which proves that the memory management performance of the system is significantly improved under high IO load, and the cpu occupation of the kswapd process is significantly reduced in the test of cpu occupation. In addition, in the current test, the server, embedded and mobile devices are also tested in scenarios. The test results show the good performance of MGLRU in memory recycling, especially in high load scenarios.

bugzilla: https://gitee.com/openeuler/open-source-summer/issues/I55Z0L

Reference:
https://lore.kernel.org/lkml/20220407031525.2368067-1-yuzhao @google.com/
https://android-review.googlesource.com/c/kernel/common/ +/2050906/10

GVPopenEuler/kernel

搜索帮助

GVP openEuler/kernel