Bikerchris
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- Joined
- Mar 22, 2020
- Messages
- 208
This might be a good video for those unfamiliar with this Filing System: https://youtu.be/lsFDp-W1Ks0
I've got to say, I do like Wendell but you're right, I suppose it was more philosophical than practical use. Still, a good intro for some I'm sure.Interesting. At 9:19 in the video, I think I see the source of the misconception (that I've addressed a number of times here recently) that RAIDZn uses dedicated parity disks (which of course it doesn't; parity is spread across all disks in the vdev). If I had a criticism, it'd be that it's much more theoretical/philosophical than practical--it gives a lot of information about the history and goals of ZFS, it's fairly light on how it works, and despite the promise in the introduction, gives almost nothing in the way of comparison to btrfs or anything else.
I think it's a valid criticism. As interesting as the video and the history are, I don't think they're going to be especially helpful for a n00b who's trying to set up a sensible ZFS pool. And I think (based both on the text Bikerchris wrote, and the place he posted it) that's how he intended it to be used (regardless of what Wendell may have intended). For that purpose, I think there are other resources that would be more helpful (many of which are already posted here). If you want an overview of the history of ZFS and what it's designed to accomplish, great. If you want to understand how to make it work for you, there are probably better resources.It's not really fair that you're criticism is around the fact that he did not go into the weeds as much as you thought he should have.
He actually uses a number of graphics (all from different sources AFAIK; they aren't original to him) that say the same thing. He himself is speaking very generally and doesn't get to that level of detail in any way. But it seems I've run across a number of people here in the not-too-distant past who believe that RAIDZ1 has one dedicated parity disk, RAIDZ2 has two, etc. I was a little puzzled about why they would think that, but when I see the graphics Wendell is using, I think the question is answered.As far as the parity thing, yeah the graphic is an incorrect oversimplification.
I think it's a valid criticism. As interesting as the video and the history are, I don't think they're going to be especially helpful for a n00b who's trying to set up a sensible ZFS pool....And I think (based both on the text Bikerchris wrote, and the place he posted it) that's how he intended it to be used (regardless of what Wendell may have intended). For that purpose, I think there are other resources that would be more helpful (many of which are already posted here). If you want an overview of the history of ZFS and what it's designed to accomplish, great. If you want to understand how to make it work for you, there are probably better resources.
To go along with my above statement, let's think about the enterprise. Rightfully or not, btrfs has a bad reputation with folks who's job it is to maintain systems in the enterprise. Whether at this point btrfs is ready for that model or not, when it was supposedly "stable" and RAID5 didn't work...People looked away and haven't come back. Wendell sums up that sentimate and seems to largely agree with alot of those who hold that opinion. He mentions btrfs as something which is a possible alternative, and states why he feels ZFS is a better choice, just like he does with NetApp and hardware RAID. I think that is good enough for the goal of his video.I also think it's a valid criticism to note that the comparison to btrfs promised in the video's introduction was pretty much nonexistent.
But again, think about it from the lens of someone who knows nothing about how ZFS, but is a sys admin in charge of a large organization. When you are managing dozens or hundreds of sites and you want to know what your options are for storage, while juggling all of your other 10,000 responsibilities, how deep down the rabbit hole are you going to go? I don't really think the distinction between having 2 dedicated parity drives or having 2 drives worth of parity being stored over all of the disks in the vdev really matters to them.He actually uses a number of graphics (all from different sources AFAIK; they aren't original to him) that say the same thing. He himself is speaking very generally and doesn't get to that level of detail in any way. But it seems I've run across a number of people here in the not-too-distant past who believe that RAIDZ1 has one dedicated parity disk, RAIDZ2 has two, etc. I was a little puzzled about why they would think that, but when I see the graphics Wendell is using, I think the question is answered.
To be very clear I am speaking for no one but myself, nor have I ever claimed to. I also am not affiliated with Level1 in any capacity.We at the Level1Techs community do not view this as trollish or zealtry behavior and just valid basic criticism. Mods please do as you will, thank you.
It's amusing that you write this after spending several paragraphs making my point for me. I suggest that you don't understand my point (despite my having stated it explicitly), which points to you defending the video against criticism I haven't made "for the sake of zealotry." I said:I just think you are being critical for the sake of zealotry.
And if you actually pay attention to the thread, you'll notice that the OP has conceded this point. It may be interesting to a lot of people, it may be useful to a lot of people, but enterprise sysadmins really didn't seem to be in view of the OP.As interesting as the video and the history are, I don't think they're going to be especially helpful for a n00b who's trying to set up a sensible ZFS pool. And I think (based both on the text Bikerchris wrote, and the place he posted it) that's how he intended it to be used (regardless of what Wendell may have intended).