* Barry Scott: > As I understand it the kernel will request that writes are not > cached. Which means that journaling file systems do in fact work well. The kernel messages I get look like this: kernel: sd 0:0:0:0: Attached scsi generic sg0 type 0 kernel: sd 0:0:0:0: [sda] 15814656 512-byte logical blocks: (8.10 GB/7.54 GiB) kernel: sd 0:0:0:0: [sda] Write Protect is off kernel: sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00 kernel: sd 0:0:0:0: [sda] No Caching mode page found kernel: sd 0:0:0:0: [sda] Assuming drive cache: write through kernel: sd 0:0:0:0: [sda] Attached SCSI removable disk kernel: sd 0:0:0:0: Attached scsi generic sg0 type 0 kernel: sd 0:0:0:0: [sda] Spinning up disk... kernel: sd 0:0:0:0: [sda] Very big device. Trying to use READ CAPACITY(16). kernel: sd 0:0:0:0: [sda] 7814035456 512-byte logical blocks: (4.00 TB/3.64 TiB) kernel: sd 0:0:0:0: [sda] 4096-byte physical blocks kernel: sd 0:0:0:0: [sda] Write Protect is off kernel: sd 0:0:0:0: [sda] Mode Sense: 53 00 10 08 kernel: sd 0:0:0:0: [sda] No Caching mode page found kernel: sd 0:0:0:0: [sda] Assuming drive cache: write through kernel: sd 0:0:0:0: [sda] Attached SCSI disk I thought that ‘Assuming drive cache: write through’ means that no barriers are used. The second one is a standard SATA drive in an USB enclosure, and those have write-reordering caches, as far as I understand it. Thanks, Florian -- _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
