Top all-time · #19683
Bart Sjerps
Personal blog · bartsjerps.wordpress.comsystemsdata
Bart Sjerps writes Dirty Cache, a personal blog at bartsjerps.wordpress.com about systems and data. Since 2014, 4 different Hacker News readers have linked it 4 times. The last post was in 2021, but the archive is still widely read.
Too few sampled comments (4) to say how often HN recommends it.?
Why HN links it
HN readers link this blog's posts on ZFS and Hammer, which measure how copy-on-write filesystems fragment Oracle database files. Commenters cite them when asking whether ZFS suits database workloads.
Summarised by Claude from a sample of 4 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
A storage infrastructure perspective on optimizing business applications
Most-linked posts?
- /2013/02/26/zfs-ora-database-fragmentation/2 people · 2 mentions · first linked 2015-01-03
What Hacker News says?
As zanny said, cow presents an issue for transactional workloads (databases, vm images, etc...) as each write fragments the file, by nature of the process of cow. btrfs can handle database workloads but you have to disable cow for them (which you can do at the file, directory, or subvolume level in btrfs). You would specify the nodatacow mount option, or chattr +C (file/directory). The btrfs autodefrag is still rath…
Comment linking /2013/02/26/zfs-ora-database-fragmentation/
on “ZFS lands in Debian contrib”According to this article, ZFS is sub-optimal for databases due to fragmentation of the db files. Could you please comment? Thx. http://bartsjerps.wordpress.com/2013/02/26/zfs-ora-database-...
Comment linking /2013/02/26/zfs-ora-database-fragmentation/
on “Is ZFS a suitable replacement for other Linux filesystems?”From that post: I will not make any comments on how this affects performance (I’ll save that for a future post). I also deliberately ignore ZFS caching and other optimizing features – the only thing I want to show right now is how much fragmentation is caused on physical disk by using ZFS for Oracle data files. Any engineer should be able to appreciate why this is frustrating from the perspective of ZFS: if you're g…
Comment linking /2014/08/11/oracle-asm-vs-zfs-xtremio/
on “ZFS vs. Hammer”I think he's referring to this: https://bartsjerps.wordpress.com/2013/02/26/zfs-ora-database...
Comment linking /2013/02/26/zfs-ora-database-fragmentation/
on “ZFS vs. Hammer”