A script I was running on avalon.dragonflybsd.org yesterday afternoon removed the packages, iso images, and snapshots stored there. (Sorry!) Hammer saved my bacon, with a snapshot of the 182G of missing files immediately available.
Category: Hammer
09/13/2009
Hammer mirror header output, just in case
If you back up the pseudo-file-systems (PFS) on your Hammer volume to a non-Hammer disk, and then need to restore them to a new Hammer volume, and then realize you forgot to write down the shared-uuid, well, then, YONETANI Tomokazu has a patch for you. I haven’t seen this committed yet, but it appears valuable.
08/22/2009
Hammer speedups
Matthew Dillon’s made some changes to Hammer that make performance during mixed operations (reading and writing requests at the same time) much faster. This should work for everyone, though AHCI/SILI/SCSI users will notice it more. The new writing system is called ‘BIOQ‘.
08/20/2009
Hammer improvements, tests
Matthew Dillon’s made some improvements to Hammer’s read and write processes. To quantize this, he’s tested Hammer and UFS with blogbench and written up the results. The tl;dr summary: UFS performs well until the system cache runs out, and then it halts. Hammer has some overhead from saving all history, but doesn’t stop working under a much heavier load.
08/15/2009
Messylaneous: books, lawsuits, git, more
Dear universe, including DragonFly people: stop doing so much stuff. It’s hard to keep up.
- Git in One Hour, an O’Reilly webcast. You need to register (free) and so on, but what the heck. O’Reilly doesn’t show crap.
- Poul Henning-Kamp is suing to recover the cost of Vista on his Lenovo laptop. (He’s installing FreeBSD.) I hope it comes out in his favor, though it will have little legal effect here in the U.S. (via)
- I didn’t realize this until I chimed in on the mailing lists, but one of the best books about file systems is freely available as a PDF.
- Another benefit of Hammer: you can’t run out of inodes, nor is it possible to have too many hardlinks.
- Some notes on pf usage in DragonFly. I know some parts have been mentioned before, but it’s good to sum up.
08/03/2009
Spreading Hammer
Want to bring Hammer to Slackware Linux? People want it, and there’s some work already in progress.
07/26/2009
PFS and NFS now play nicely together
It is now possible to mount a Hammer PFS via NFS, though you’ll want to use NFSv3.
07/24/2009
Hammer gets bigger
Hey, look at what Michael Neumann’s doing: making Hammer expandable! It will be possible to expand your Hammer volumes while online, even.
(note: it’s experimental; don’t be surprised if it destroys data.)
07/11/2009
New Hammer option
The hammer command now has an ‘info’ option, which gives a great deal of information on your Hammer drives, thanks to Antonio Huete Jimenez. (Committed)
06/29/2009
New Hammer version
Matthew Dillon has a new version of Hammer, which speeds up listings from programs like ‘ls -la’ and ‘find’. This is only in 2.3.1.x code right now, so don’t force an upgrade via hammer version-upgrade if you’re still on DragonFly 2.2. His post includes some benchmarks.
On a side note: sili(4) tests look good.
06/28/2009
Other ways to back up Hammer
As Jim Chapman found out, dump only works for UFS, and not for Hammer. Matthew Dillon outlined the different mirroring and snapshot methods that Hammer makes available.
06/25/2009
Mirroring with Hammer
Siju George described his efforts to set up a continuous, automatic backup system using Hammer, with some interesting results. Matthew Dillon chimed in with some suggestions.
06/21/2009
Minor Hammer changes
Matthew Dillon’s made some small changes to Hammer; it should result in a small speedup when copying data.
06/19/2009
Better speed for cleanup
A number of people have noticed that Hammer’s pruning (which by default runs once at midnight) makes systems temporarily unresponsive. Matthew Dillon’s committed a fix for this, with warnings of more improvements to come.
06/17/2009
Bulk build speed stats
I recently did a bulk build of pkgsrc on two similar machines; the only significant difference being extra CPU work being done on one system, and Hammer snapshots on the other. However, they’re diverging in speed over time, which is interesting but not yet conclusive. Read my post about it for more details.
A good benchmarking project would be testing Hammer with snapshots on and with snapshots off.
05/26/2009
Hammer presentation at BSDDay
Sdävtaker is giving a “Hammer administration” presentation at BSDDay, May 29th and 30th in Argentina. (His presentation is the second day.)
05/13/2009
Hammer porting notes
Daniel Lorch, the student working on a port of Hammer to Linux, has a blog, with some notes on progress. I found this April item entertaining.
05/12/2009
lseek(2) extensions for Hammer?
Pedro F. Giffuni suggested that the SEEK_HOLE and SEEK_DATA lseek extensions would be good additions to Hammer, and linked to a Sun paper that went into more detail.
04/17/2009
Encryption ideas for backups
Sdävtaker came up with a potential idea for encrypting backup files, and Matthew Dillon followed up with another way that uses Hammer.
04/16/2009
Hammer for Linux, and others
Daniel Lorch is working on a port of Hammer to Linux’s VFS, though since he’s using FUSE, it will be able to reach other systems, like NetBSD. The code is accessible.
04/14/2009
Lost any Hammer files?
Matthew Dillon is trying to track down a Hammer bug where directory entries (files, usually) are missed, whether it’s with ls or find or similar. Has this happened to you? It’s apparently very hard to duplicate, so please speak up if it has.
03/30/2009
DWIMmy undo
Hammer’s ‘undo’ now has the ability to index and automatically diff historical versions of files for you, thanks to a patch from Joel K. Pettersson. (He’s got more ideas, too.
03/25/2009
Hammer for Linux?
Simon ‘corecode’ Schubert has a student working on a Linux port of Hammer. This will lead to a breakout of Hammer from the DragonFly tree, too.
03/16/2009
New Hammer feature
Matthew Dillon has added a “rebalance” feature to Hammer, which cleans up the underlying B-Tree structures in Hammer that might otherwise slow down searching. It’s considered experimental, so be careful with it for now.
03/12/2009
Messylaneous, 03/12/2009
A bunch of links, cause that’s the easiest way to get this all out:
- ‘Beket’ has added a vkernel debugging howto on the DragonFly site.
- The Open64 compiler may work may work with some tweaking on DragonFly.
- And llvm/clang too.
- You can use BSD almost any way you want. Linux, not so much. (via)
- Hammer softlinks can now be represented in a shorter form.
02/25/2009
Hammer this, Hammer that
Hammer filesystem, meet Hammer OS. Please don’t take this seriously.
