<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 3 Jun 2023, at 5:07 am, James Abernathy <<a href="mailto:jfabernathy@gmail.com" class="">jfabernathy@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div dir="ltr" class=""><br class=""></div><br class=""><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jun 2, 2023 at 9:11 AM James <<a href="mailto:jam@tigger.ws" class="">jam@tigger.ws</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div style="overflow-wrap: break-word;" class=""><br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On 2 Jun 2023, at 8:59 pm, James Abernathy <<a href="mailto:jfabernathy@gmail.com" target="_blank" class="">jfabernathy@gmail.com</a>> wrote:</div><br class=""><div class=""><div dir="ltr" class=""><div dir="ltr" class=""><br class=""></div><br class=""><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jun 2, 2023 at 8:33 AM James <<a href="mailto:jam@tigger.ws" target="_blank" class="">jam@tigger.ws</a>> wrote:<br class=""></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class=""><br class=""><div class=""><br class=""><blockquote type="cite" class=""><div class="">On 2 Jun 2023, at 8:08 pm, Richard Shaw <<a href="mailto:hobbes1069@gmail.com" target="_blank" class="">hobbes1069@gmail.com</a>> wrote:</div><br class=""><div class=""><div dir="ltr" class=""><div dir="ltr" class="">On Fri, Jun 2, 2023 at 6:54 AM James <<a href="mailto:jam@tigger.ws" target="_blank" class="">jam@tigger.ws</a>> wrote:<br class=""></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class=""><div class="">There is quite a lot of discussion on why not to use btrfs with maria<div class=""><a href="https://gitlab.archlinux.org/archlinux/infrastructure/-/issues/58" target="_blank" class="">https://gitlab.archlinux.org/archlinux/infrastructure/-/issues/58</a></div></div></div></blockquote><div class=""><br class=""></div><div class="">There's a few different solutions if you already have the files created since the +C must be done at creation.<br class=""></div><div class=""><br class=""></div><div class="">My method is to:<br class="">mv <file> <file>_backup</div><div class="">touch <file></div><div class="">chattr <a class="gmail_plusreply" id="m_6148784532034167808m_-6087249095224027248plusReplyChip-1">+C <file></a></div><div class="">dd if=<file>_backup of=<file></div><div class=""><br class=""></div><div class="">You can add bytesize (bz=1M) or similar to speed it up. I did this with a 1TB blockchain file successfully.</div><div class=""></div></div></div></div></blockquote><br class=""></div><div class="">Mostly for Jim Abernathy's info, I pretty much stick to ext4, but was toying with idea of changing</div><div class=""><br class=""></div><div class="">James</div></div></blockquote><div class=""><br class=""></div><div class="">I've used btrfs in a RAID 1 mirror array on my production backend with mariadb for a year plus a few months without issues. I update about once a month and that usually requires a reboot. The boot ssd also was installed with btrfs with timeshift snapshots every hour.</div><div class=""><br class=""></div><div class="">I didn't do anything about COW disable at the time of install. I see from the archlinux link that someone said it was addressed 2 years ago??? If that's true, should I even need to worry about chattr <a class="gmail_plusreply" id="m_6148784532034167808plusReplyChip-0">+C <file>???</a></div><div class=""><br class=""></div><div class="">I learned most of what I know about BTRFS usage from the Kubuntu Forum. They have a BTRFS category and I'll ask for knowledge over there.</div><div class=""><br class=""></div><div class="">I make special arrangements for COW issues for Virtual Machines by keeping all qcow2 files on a separate ssd formatted ext4. I think that is required because qcow2 files already use COW. I prefer this instead of chattr +C /var/lib/libvirt/images. Using a separate ext4 ssd has the added benefit of not having to recreate VMs when I change Distro every month or so because some defect in my brain requires it.</div></div></div></div></blockquote><br class=""></div><div class="">Jim if you uncover anything interesting please post it (or even just mail me)</div><div class="">thanks</div><div class="">James</div></div></blockquote><div class=""><br class=""></div><div class="">I did discover that a normal install of mariadb-server on Kubuntu 23.04 on a btrfs volume does NOT set the COW disable attr. I was able to mkdir -p /var/lib/mysql first and the chattr +C /var/lib/mysql before the apt install mariadb-server and that does setup all the right COW disable bits.</div></div></div></div></blockquote><div><br class=""></div>Hmm 2 thread benchmark in the 350 transaction range; maybe mythtv is a heavy user</div><div><a href="https://dba.stackexchange.com/questions/311348/mariadb-benchmarking-low-transaction-and-query-per-second" class="">https://dba.stackexchange.com/questions/311348/mariadb-benchmarking-low-transaction-and-query-per-second</a></div><div><br class=""></div><div>James<br class=""></div><br class=""></body></html>