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Who Needs Git When You Have ZFS?

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Re: Who Needs Git When You Have ZFS?

#91

Post by Kurtz79 »

pmarreck wrote: post #55
raverbashing wrote: post #5

> Who needs Git? > Notably missing is support for merging So, it's almost like a car except it's missing its wheels No, it's not like Git

I really don't think the article was seriously suggesting what you think it was; showing similarities between different types of tools (usually a more familiar one and a less familiar one) is meant to be illustrative

"I really don't think the article was seriously suggesting what you think it was"

Then maybe it shouldn't have a purposefully click-baitingly title suggesting it does...

Re: Who Needs Git When You Have ZFS?

#93

Post by drvdevd »

devonkim wrote: post #59

I've been working with virtual machines in production and development for well over a decade now and a lot of what works via ZFS in this article works very similarly to how it would work we used AWS or VMware style snapshots. In fact, ZFS snapshots are only so helpful if you make complicated changes across multiple ZFS volumes, for example, that require some more transactional style rollbacks. In such scenarios, it m…

Actually, perhaps this doesn't address all your points, but I share the sentiment about VM snapshots "feeling" quite similar, in fact I experience it every day as I run ZFS as a root filesystem within VMware. The real gain for me is that all of these tools are in-band with my working OS. If I were provided a VM(s) on AWS or some SAN by my employer, that could in theory give us a mutual benefit. Ops could avoid giving me access via IAM or whatever and expanding beyond some set limit, but allow me to perform almost identictal "ops like" tasks using ZFS (which I also find to be fairly user friendly).

Incidentally, I'm also a fan of nested virtualization and using git on top of ZFS... I believe all of these tools complement each other nicely as opposed to being mere repetitions.

Re: Who Needs Git When You Have ZFS?

#94

Post by jaredklewis »

kennywinker wrote: post #89
linsomniac wrote: post #88

I'm tempted to write an article: Who Needs ZFS When You Got Git, but the title IS the article. Don't get me wrong, I looove ZFS, and from a quick scan this article looks like a good intro to ZFS, particularly for someone familiar with git.

Author is not actually suggesting replacing your version control with ZFS. From the first paragraph: > Of course, I'm not seriously suggesting you'd ditch a "proper" version control system, but it gives a good sense of what's possible at the file system level.

I like how he uses of course . "Of course," the title of this article is misleading. The article is about something different, but this was the most clicky baity combination of words including "git" and "zfs."

Re: Who Needs Git When You Have ZFS?

#95

Post by Ericson2314 »

An important difference is that While both rely on Merkel DAGs git uses content addressing while ZFS doesn't (physical addresses impact hash too).

Relatedly, ZFS's memory management relies on the assumption that a forked filesystem and its sibling will monotonically alias less data as either is modified. This allows it to avoid tracing and ref-counting alike, but makes implementing merging or `cp --reflink` difficult.

Re: Who Needs Git When You Have ZFS?

#96

Post by mikestew »

kennywinker wrote: post #89
linsomniac wrote: post #88

I'm tempted to write an article: Who Needs ZFS When You Got Git, but the title IS the article. Don't get me wrong, I looove ZFS, and from a quick scan this article looks like a good intro to ZFS, particularly for someone familiar with git.

Author is not actually suggesting replacing your version control with ZFS. From the first paragraph: > Of course, I'm not seriously suggesting you'd ditch a "proper" version control system, but it gives a good sense of what's possible at the file system level.

So the title is click-bait, then? I almost read the article, but in the 342 milliseconds between thinking that and reaching for the mouse, I came up with three reasons the topic alluded to in the title would be a dumb idea. And it turns out that's not what the article is about anyway.

Re: Who Needs Git When You Have ZFS?

#97

Post by belorn »

hhw wrote: post #86
liotier wrote: post #81

Earlier quoted context omitted.

> CDDL is an open-source licence just as the GPL But incompatible with the GPL, which mostly explains the current situation of ZFS on Linux.

It's the GPL that's incompatible with the CDDL and not the other way around, which is an important distinction. Other than other GPL variants and BSD and MIT style licenses, the GPL has restrictions which make it pretty much incompatible with everything.

I don't get how the word "incompatible" can be understood as anything other than both license has aspects which makes combining them impossible. But owell, lets see what the license text actually say:

Any Covered Software that You distribute or otherwise make available in Executable form must also be made available in Source Code form and that Source Code form must be distributed only under the terms of this License. The Modifications that You create or to which You contribute are governed by the terms of this License.

If you distribute source code, this license means that you must use this license. You can't use some other license, as its not compatible with the distributor deciding what license to use. CDDL license require that any source code distribution use CDDL as its license, and it is incompatible with any other license that has similar condition. CDDL is incompatible with GPL because GPL has similar conditions as CDDL.

If we were to make an identical copy of the CDDL license and call it CDDLv2, those two identical twins would be incompatible with each other. Software under CDDLv1 would not be permitted to be combined with software under CDDLv2 and distributed as source code.

Re: Who Needs Git When You Have ZFS?

#98

Post by BinaryIdiot »

Kurtz79 wrote: post #91
pmarreck wrote: post #55

Earlier quoted context omitted.

I really don't think the article was seriously suggesting what you think it was; showing similarities between different types of tools (usually a more familiar one and a less familiar one) is meant to be illustrative

"I really don't think the article was seriously suggesting what you think it was" Then maybe it shouldn't have a purposefully click-baitingly title suggesting it does...

Considering the audience I think it's fine. I don't think anyone on HN is going to see this title and think "oh the author is serious; this whatever thing that appears to be a file system by name can certainly replace git in its entirety!"

Re: Who Needs Git When You Have ZFS?

#99

Post by ryao »

espadrine wrote: post #74
ryao wrote: post #64

Earlier quoted context omitted.

Oracle sued over Google reimplementing code that was under the GPL (OpenJDK) under the Apache 2.0 license (Apache Harmony). Google recently switched to the GPL code because of it. In the case of ZoL, the code is derived from the original code and is under the original license. The idea that ZoL is somehow more at risk is pure FUD.

My understanding is that the risk is mostly the other way around: it infringes Linux' GPL license (see https://sfconservancy.org/blog/2016/feb/25/zfs-and-linux/ ). Would Oracle have grounds to sue as a Linux copyright holder? They have successfully made API copyrightable, so they clearly have competent lawyers.

There are a few people who think that. There are plenty of others who do not. Those in charge of reviewing licensing in Linux distributions that have adopted it are generally of the opinion that it is okay, especially those in charge of Sabayon and Ubuntu. Gentoo came to similar conclusions long before them (>4 years before Ubuntu) and ships it in binary form on the LiveDVD. At this point, there are at least a few dozen distributions that have adopted ZFS in some form or another.

Here is a legal opinion on the matter:

https://www.softwarefreedom.org/resources/2016/linux-kernel-...

Re: Who Needs Git When You Have ZFS?

#100

Post by ryao »

linsomniac wrote: post #88

I'm tempted to write an article: Who Needs ZFS When You Got Git, but the title IS the article. Don't get me wrong, I looove ZFS, and from a quick scan this article looks like a good intro to ZFS, particularly for someone familiar with git.

When KDE's git repositories had been corrupted, one server being out of sync was the only thing that saved it. ZFS could have saved it and as far as I know, one mirror administrator is using ZFS to protect KDE's git repositories against recurrences.

ZFS and git are complementary technologies. One does not replace the other.

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