allanjude

5 ms·

1.
by allanjude 8mo ago
RAID would only be able to recover if it KNEW the data was wrong. Without a checksum, hardware RAID has no way to KNOW it needs to use the parity to correct the block.
2.
by allanjude 10mo ago
klarasystems.com | OpenZFS Developer | REMOTE | Full-time Contract We successfully hired from HN in the previous round and are looking for another OpenZFS Developer (3+ years of experience) to join our team! Klara Inc. provides development
3.
by allanjude 1y ago
Klara Inc. | OpenZFS Developer | Full-time (Contractor) | Remote | https://klarasystems.com/careers/openzfs-developer/ Klara provides open source development services with a focus on ZFS, FreeBSD, and Arm. Our mis
4.
by allanjude 1y ago
The "M" at the end of that revision number suggests a "modified" tree, meaning they had their own patches that were not part of the upstream repository as well.
5.
by allanjude 2y ago
ZFS has supported online adding of vdevs since the start too, this is specifically modifying an existing vdev and widening it, which is much less common, and much more complex
6.
by allanjude 2y ago
There are advantages to doing the cloning at the block level, rather than the VFS layer. The feature was originally written for FreeBSD using the copy_file_range() syscall, then extended to work with the existing interfaces in Linux from bt
7.
by allanjude 2y ago
There are a few different use cases, but cloning a VM image file is definitely a popular one. Also, `mv` between different filesystems in the same ZFS pool. Traditionally when crossing filesystems doesn't allow just using `rename()`, `
8.
by allanjude 2y ago
It is, except it lets you do it as a sub-file level. You can clone a (block aligned) byte range of a file using the copy_file_range() syscall
9.
by allanjude 3y ago
That is not how this will work. The reason the parity ratio stays the same, is that all of the references to the data are by DVA (Data Virtual Address, effectively the LBA within the RAID-Z vdev). So the data will occupy the same amount of
10.
by allanjude 3y ago
A post where we discuss some strategies and tools to make managing disk arrays on FreeBSD (and related platforms like TrueNAS Core) much easier. These concepts also apply to other operating systems, but the tools might differ slightly.
11.
Tips for Managing Disk Arrays on FreeBSD(klarasystems.com)
2 points by allanjude 3y ago|1 comments
12.
by allanjude 4y ago
This was a bug in ZFS itself, and was resolved years ago: https://smartos.org/bugview/OS-6404 In FreeBSD 12.x and older, you could opt out of using UMA with: vfs.zfs.zio.use_uma=0, but that is not necessary
13.
by allanjude 5y ago
The metadata of the zvol on the host pool, does benefit from the metadata vdev (NOT A CACHE)
14.
by allanjude 5y ago
The metadata vdev is not a cache, it is the primary store. Too many years of thinking of the aux vdev types like SLOG and L2ARC as caches, has made people confuse this one frequently.
15.
by allanjude 5y ago
In previous talks Netflix has mentioned that due to serving so many 1000s of people from each box, that they basically do 0 caching in memory, all of the system memory is needed for buffers that are enroute to users, and they purposely avoi
16.
by allanjude 5y ago
The videos should appear on the conference's youtube channel in a few weeks: https://www.youtube.com/eurobsdcon
17.
by allanjude 5y ago
I think the implication is: TCP kind of assumed you will either keep transmitting, or close the connection. The many video-streaming type workloads, the connection will go idle, for seconds or even minutes at a time. If the loss is at the t
18.
by allanjude 5y ago
Integrated with Kernel, vs not. Other tools in the OS that can take advantage of ZFS, vs not.
19.
by allanjude 5y ago
For example, on Solaris and FreeBSD, it is possible to force-unmount a filesystem. on Linux it is not.
20.
by allanjude 5y ago
Sure, the ZFS features are the same, but the integration is still not all there on Linux, and is on FreeBSD. FreeBSD has features like 'bootonce', to switch ZFS boot environments on the next boot only. Better integration with the
21.
by allanjude 10y ago
VIMAGE / VNET, which allow you to have an instance of pf for each jail. Very useful
22.
by allanjude 10y ago
iianm, Solaris has a port of IPF, not pf. Oracle is working on trying to port pf now.
23.
by allanjude 10y ago
Is it really though? It is running on top of a stripped down version of Redhat.
24.
by allanjude 12y ago
You can always email the guest. We include the guest's contact details in every episode's show notes.
25.
by allanjude 12y ago
This is one of the reasons for the existence of the 'toor' user, which still uses the default shell
26.
by allanjude 12y ago
A feature similar to this was discussed at the OpenZFS Developers Summit earlier this month http://open-zfs.org/w/images/7/71/Fast_File_Cloning-Pavel_Za...
27.
by allanjude 12y ago
Ohh, and Re: ZFS using a lot of ram: You can limit it. The default is 95% of ram, and that is too high in all cases except a dedicated file server. PCBSD in 10.1 (released this week), changed the default to be much more conservative, since
28.
by allanjude 12y ago
FreeBSD changed how the packages work last year You now get the regular repository (binary packages updated once per week), or the 'Quarterly Branch' (a known-good snapshot of the packages, with security updates) Or you can build
29.
by allanjude 12y ago
Netflix does contribute, in addition to money paid to the foundation, they also have quite a few developers working on FreeBSD almost full time. You can see lots of commits with 'Sponsored by: Netflix'. nginx and Yandex also do a