------- Comment From bren...@br.ibm.com 2018-04-02 08:58 EDT------- (In reply to comment #45) > IBM, Can you please update this bug when this patch lands upstream?
Yes, but I do not think we can make 18.04 anymore. Deferring to 18.10. ** Tags removed: targetmilestone-inin1804 ** Tags added: targetmilestone-inin1810 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to zlib in Ubuntu. https://bugs.launchpad.net/bugs/1742941 Title: zlib: improve crc32 performance on P8 Status in The Ubuntu-power-systems project: Incomplete Status in zlib package in Ubuntu: New Bug description: Calculate the checksum of data that is 16 byte aligned and a multiple of 16 bytes. The first step is to reduce it to 1024 bits. We do this in 8 parallel chunks in order to mask the latency of the vpmsum instructions. If we have more than 32 kB of data to checksum we repeat this step multiple times, passing in the previous 1024 bits. The next step is to reduce the 1024 bits to 64 bits. This step adds 32 bits of 0s to the end - this matches what a CRC does. We just calculate constants that land the data in this 32 bits. We then use fixed point Barrett reduction to compute a mod n over GF(2) for n = CRC using POWER8 instructions. We use x = 32. http://en.wikipedia.org/wiki/Barrett_reduction To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1742941/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
