I have been using NextCloud for a long while now. It is a smart solution, and although I do not like its agent (I’ve had many problems with it around Hebrew file names on multiple types of operating systems, which never matured enough for a full bug description and details) – for an easy access…
A nice and informative note about how to obtain OracleASM attributes, including “hidden attributes” can be found here. Including the special attribute “_rebalance_compact” which affects the post-rebalance ‘compact’ ASM operation, when altering DiskGroups (per-DiskGroup, of course). Just a reminder about this specific attribute – when ASM performs rebalance operation (adding or dropping disks) it attempts…
After one of the recent updates, a few KVM-based systems could not boot anymore. I am using ZFS for my emulated block devices, and I was happy with that until recently. Now – VMs won’t start, showing the error message in this post’s header. The source of the problem is rather nasty – qemu update…
The IO scheduler blk_mq was designed to increase disk performance – better IOps and lower latency – on flash disk systems, with emphasis on NVME devices. A nice by-product, is that it increases performance on the “older” SCSI/SAS/SATA layer as well, when the disks in the back are SSD, and even when they are rotational…
Every Linux admin is familiar with the long time running through a large directory tree (with hundred of thousands of files and more) can take. Most are aware that if you re-run the same run-through, it will be shorter. This is caused by a short-valid filesystem cache, where the memory is allocated to other tasks,…
All ZFS users are familiar with ‘zpool iostat’ command, however, it is not easily translated into Linux ‘iostat’ command. Using large pools with many disks will result in a mess, where it’s hard to identify which disk is which, and going to a translation table from time to time, to identify a suspect slow disk….
