Observations from some very unscientific testing. Testing was done with fio using 8 parallel jobs doing random reads in an amd64 VM with 8 cores.
* The kernel in comment #10 and 4.4.0-45 (with SQUASHFS_DECOMP_MULTI_PERCPU) performed comparably for the most part. 4.4.0-47 (with CONFIG_SQUASHFS_DECOMP_SINGLE) was somewhat slower. * With 4K and 128K block sizes, I did not see the kernel from comment #10 falling back to using the data block cache at all during my tests. With a 1M block size it was falling back to the data block cache sometimes. -- 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/1636847 Title: unexpectedly large memory usage of mounted snaps Status in Snappy: New Status in linux package in Ubuntu: Fix Committed Status in linux source package in Xenial: Fix Released Status in linux source package in Yakkety: Fix Committed Status in linux source package in Zesty: Fix Committed Bug description: This is a tracking bug for what might be kernel bugs or kernel configuration changes. As described [1], memory used by simply mounting a squashfs file (even an empty one) is ranging from almost nothing (on certain distributions) to 131MB on Ubuntu 16.04 and 16.10 on a single-core machine or VM. The amount is excessive and should be investigated by the kernel team. We may need to change the kernel or at least the configuration we ship in our packages and kernel snaps. [1] https://github.com/zyga/mounted-fs-memory-checker To manage notifications about this bug go to: https://bugs.launchpad.net/snappy/+bug/1636847/+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
