Comment by lewisjoe
5 years ago
I'm part of the team that makes Zoho Writer (a Google Docs alternative) - https://news.ycombinator.com/item?id=24186883
However, in the spirit of "There are no solutions, only trade-offs" CRDTs are absolutely necessary for certain type of syncing - like syncing a set of database nodes.
But for systems which already mandate a central server (SaaS/Cloud) and especially for a complex problem like rich-text editing (i.e semantic trees) I still think OT provides better trade-offs than CRDT.
I respect Joseph's conviction on CRDTs being the future, so I guess we'll figure this out sometime soon.
My small startup company went with Zoho office at first because of the price. But the features is what has us looking to stay for a while.
One thing I would love to see is the addition of wildcard addresses like the way google has and microsoft added (user+site_string@domain.com).
Thanks for your hard work on a great product!
The Zoho ecosystem is this weird place where you can find almost everything, virtually for free. If you’ve never looked before, check it out - it’s expansive.
Frustratingly though, there are so many features heaped in that there is no cohesion. Things are frequently buggy, unreliable and disjointed. I’d almost be able to forgive it but unfortunately the support is really terrible too.
I assessed a lot of crm software and each one I kept finding things they didn’t have that zoho had but for the reasons above we ultimately chose something else. Which is a shame, because I would pay them a lot more than they ask, for them to just be a little better.
> Things are frequently buggy, unreliable and disjointed. I’d almost be able to forgive it but unfortunately the support is really terrible too.
This is my experience. After years of paying for the service, for multiple users, using tools that seemed to have been forgotten by the dev team, my credit card failed to process one month.
Support was not interested in helping me. Not at all. Ended up having to move my team's workflow off Zoho. I had been begging them to bill my card, but they just kept sending me generic emails asking me to try again. Phone support was even less helpful.
Preceding comment like this with OT goes a long way.
We went with OT five years ago in CKEditor 5 and we have the same experience. While it would be tempting to try CRDT, it seems to come with too significant tradeoffs in our scenario.
My colleague wrote down our thoughts in https://news.ycombinator.com/item?id=24621113. With OT, if we get the corner cases right, we can tune and extend the implementation. With CRDT that might be game over.
Interesting. I might be adding real-time edit syncing to a hobby project sometime soon. Can you share more about the trade-offs?
I haven't yet completely watched Martin's talk on CRDTs, so I might come back and stand corrected. For now these are some well known trade-offs
A central server: Most OT algorithms depend on a central system for intention preservation. CRDTs are truly distributed and need no central server at all.
Memory: Traditionally CRDTs consume more memory because deletions are preserved. OT lets you garbage collect some operations since a central system is already recording those ops and sequencing them as well.
Analysing and cancelling ops: OT lets you easily analyse incoming ops and modify/dummy-ify/cancel them without breaking the consistency. This convenience is not necessary for most cases, but really important for rich-text editing. For example when someone merges a couple of table cells when another user is deleting a column, we need to analyze these operations and modify them so as not to end-up with an invalid table structure.
For building P2P / decentralized apps, could OT be used with some kind of leader election system?
2 replies →
Seems like another one (based off the article) is ease of use as well. I'm not familiar with either algorithm, but sounds like OT is less complex and easier to understand, which IMO is a decent tradeoff worth considering.
4 replies →
Dealing with text is still an active area of research for CRDTs. While the problem has been theoretically solved, the solutions require much more memory/bandwidth than OT does.[1] Conversely, CRDTs are significantly better at replicating graphs.
yjs[2] is one CRDT that handles text reasonably well, but it can still run into performance edge cases (as they plainly/honestly admit in their README).
[1]: https://github.com/automerge/automerge/issues/89 [2]: https://github.com/yjs/yjs
Have you watched the presentation referenced in the article? CRDTs have come a long way. You can get down to about a 150% increase in size over a plain text representation. Since most rich text formats store the edit history anyway, this is closer to feasible than the numbers might suggest.
The transform operation is more simple if you know the order of things. For example in OT: nr2) Delete H from index 0. nr1) Insert "Hello" at index 0. You know that nr1 should come before nr2 because of a central counter. But with CRDT it's a) Delete character id 0, b) Insert "Hello" at character with id 0.
I think intention preservation requires that you know what the clients know about. So you still need something like a vector clock to model what the dependency relationship between nr2 and nr1 are.
1 reply →
What does OT stand for?
In the link, OT is aliased to "Operational Transformations"
Have you not answered your own question? OT does indeed stand for Operational Transformation.
https://en.wikipedia.org/wiki/Operational_transformation
"Operation Transformation" = "a system that supports collaboration functionalities by separating the high-level transformation (or integration) control from the low-level transformation functions"
Source: OT's Wikipedia article
But I felt the same. Never heard of "Operation Transformation" before and both OT and its alias were equally opaque to me.
Don't click on a link if you're unsure - from the title or URL - the content is relevant to you.
It's equally "disrespectful" to waste reader's time on 101 content if that's now what the post is about.