When editing and saving extremely long posts (around 100,000 characters), we encountered a backend timeout issue. The server becomes unresponsive during the save operation, resulting in 502/504 errors. The frontend console shows the following error stack: ajax-error.js:36:15 l ajax-error.js:36 u aj…

In Feb I added `diff_too_complex: “The diff is too complex to display. Please try viewing individual smaller edits.”` Our diff algorithm will just stop if stuff gets too complicated. Are you running latest here? It should handle these cases, unless you have a very very under-powered server.

Meanwhile, the server-side Unicorn logs captured the exact point of the timeout, confirming that the worker was killed while processing the markdown diff: Unicorn worker received USR2 signal indicating it is about to timeout, dumping backtrace for main thread config/unicorn.conf.rb:204:in `backtrac…

Can I resolve the above issue by changing UNICORN_TIMEOUT to 60 or 120?

Hey, I think I’ll move this to Contribute > Bug . 100k chars is very unusual but regardless, some fallback should be implemented I think.

I was on the early version from this year earlier, but I just upgraded to the absolute latest version! After the upgrade, I successfully saw the “The diff is too complex to display” message, and honestly, it’s awesome. At least it doesn’t hard-crash and still allows me to go ahead and delete edit h…

Amazing :+1: I believe the “diff too complex” threshold can be tweaked, so if you feel there is such a need, we can figure it out :+1: (there’s a lot of factors to take into account, so there might not be a one-size-fit-all solution)

I have tested this multiple times now. Even with edits complex enough to trigger the “The diff is too complex to display” notice, the post has never failed to publish again. I believe this issue has been completely resolved in the latest version. Thanks again to the team for the great work!

保存长文章（约10万字）的大段编辑时，因Diff瓶颈导致后端出现502/504超时

支持

chapoi 2026 年6 月 22 日 07:31 4

嘿，

我想我会把这个问题移到 #contribute:bug。10 万字符非常不寻常，但无论如何，我认为应该实现某种回退机制。

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保存长文章（约10万字）的大段编辑时，因Diff瓶颈导致后端出现502/504超时

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