"Project Springfield" Is Red Hat's Effort To Improve Linux File-Systems / Storage

[elatllat]

Eh. The issue is CPU power...

maybe for you, I found ceph pleasantly lights on my CPUs unlike say cockroachdb.
+adding more nodes should address speed issue, but like I said the main advantage is continuous up time.

[pal666]

Yeah, as a general rule "Btrfs has some performance issues with any drives when compared to EXT4 or even NTFS under windows.", ZFS (the only other filesystem that has a similar feature set) is much better if you have some spare RAM to act as cache.

bullshit on both accounts(ext4 should be on top of lvm snapshots obviously)

[pal666]

LVM and friends have none of those issues and do have many (all?) the advantages of those two advanced local file systems;
like adding space to a volume without downtime, snapshots before risky operations or backups, lvmcache, shrinking volumes to mess with other file systems like btrfs,ceph,etc.

lvm snapshots are much slower than btrfs. btrfs raid1 can autoheal, ext4 on block layer raid1 can't. flexible block mapping part of lvm is really good though, i have two separate btrfs filesystems on lvm to compensate for still existing limitation of only one raid level per btrfs filesystem.

[pal666]

the fs is in the LVM partition/volume, there is no "underlying" fs in LVM.

i'm sure he meant the opposite - lvm is under fs

LVM has no concept of RAID. You use it on top of Mdadm RAID.

lvm's concept of raid is called dmraid

[pal666]

Maybe they'll realize NILFS2 exists, is in the Linux kernel, has data and metadata checksums, does snapshots

readonly snapshots and no subvolumes

and, most important, is designed for Low Latency.

no, it was designed for flash. i.e. it's a competitor to f2fs, not to btrfs, which has much more features

But that's overly optimistic, chances are they'll just continue to go full retard with that BTRFS trash.

i'm pretty sure they aren't as clueless as you

[pal666]

But if you want to shuffle file systems LVM is your friend and once you are already using LVM (and cryptsetup) the advantages of btrfs diminish. When btrfs gets encription and caching it will make choosing between it and LVM&friends easier..

i use btrfs on lvm and lvm reduces btrfs advantages by zero amount(its snapshots and raids are inferior to btrfs). lvm just adds one unique advantage to btrfs

[pal666]

That's a frontend for the same kernel's software RAID subsystem just as mdadm is. It's just a different userspace tool.

all of lvm is a userspace tool frontend for kernel subsystem device mapper. just like dmraid and unlike mdadm

[pal666]

The commit counts are similar;

# git clone --branch linux-5.4.y https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
# cd linux
# git log --since="2019-11-25" --grep="ext4" --pretty=oneline | grep -c ext4
50
# git log --since="2019-11-25" --grep="btrfs" --pretty=oneline | grep -c btrfs
91

considering btrfs has much larger scope, i's say it has fewer bugs than ext4 per feature

But the severity must differ because I've had, and read more people having, data loss due to bugs on btrfs than ext4.

after 2019-11-25?

[pal666]

Well if you want to apply the weekly kernel bugfix without interrupting your better half watching a vid from your SAN,

do it at night?

[elatllat]

do it at night?

Thou shalt not screen while one's other half is not screening.