------- Comment From h.carst...@de.ibm.com 2019-08-30 07:12 EDT------- ------- Comment From h.carst...@de.ibm.com 2019-08-30 07:52 EDT-------
------- Comment From h.carst...@de.ibm.com 2019-08-30 16:25 EDT------- -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1841193 Title: s390x load + decompress time of kernel image with lz4 is 2x slower than lzo Status in Ubuntu on IBM z Systems: Fix Released Status in linux package in Ubuntu: Fix Released Bug description: Canonical Kernel Performance Team has been doing benchmarks on loading & decompressing time of the kernel images to select the fastest compression. On x86_64 lz4 came out as the best one. On our s390x load + decompress time of kernel image with lz4 appeared to be 2x slower than lzo. Tested on z13 mainframde, whilst kernel is compiled targetingging -march=zEC12. Which is a bit surprising. Are there any performance improvements that can be done to kernel lz4? You can see assessment details over at the public bug https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1840934 I wonder if IBM teams can try different kernel compression algorithms to doublecheck that indeed load+decompress time of lzo kernel image is the fastest, and faster than lz4 or gzip. Also, would that change with z14 and the hw accelerated decompression there? Is that implemented for the kernel decompressors? We will be switching kernel image compression to lzo with the v5.3 kernel on s390x. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1841193/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
