It takes a long time to open a big pull request page

[ffbh123456]

Gitea version 1.14.0+dev-449-ge0c753e77 built with GNU Make 4.3, go1.15.6 : bindata, timetzdata, sqlite, sqlite_unlock_notify

The gitea server is deployed locally. I made a pull request and changed more than 100 files and more than 1,000 lines. It took me nearly two minutes to open this pull request page.
I looked at the log, mainly because these two API return very slowly, both of which are about one minute
Are there any configuration items that can improve the speed here?

[lunny]

How many files and lines changed on this PR?

[tomaswarynyca]

An example https://gitea.com/gitea/tea/pulls/316/files

I think you should put a limit to the amount of content displayed and if the user requires more by clicking on a button to load more content.

[ffbh123456]

@lunny
100 file, 1000 add line, 1000 delete line, every file about 10 add line and 10 delete line.

[PhenX]

I agree that the pull request page can be very hard to use, even more when dealing with many files. One solution would be to show a tree of the modified files and show the diff when clicking on those files. We had this on bitbucket and that was really better than to have everything on the same page.
This would solve the problem for this kind of pull request, and I personally find it way better.
All my colleagues agree with this, they miss this feature.

[bartkaptur]

Same problem here. Setting DISABLE_DIFF_HIGHLIGHT = true helps, but only gets you so far. The HTML generated for a pull request is highly complicated and gets huge quickly. A new, simplified mode for this view would be useful.

[primesun]

In my opinion the ideal solution would be to have a file tree on the pull request page, and you would click to select one file diff at a time.

[PhenX]

Hello, to follow up on my last message about the pull request page, I started a project built on AspNet Core (5.0, but might work easily on 3.1 or even 2.1 as the backend is rather simple, no database required, everything is done via API) and VueJS for the front end.

It uses the Gitea API to provide :

• Authentication
• A list of the connected user's accessible pull requests or only the ones for which he's a reviewer
• A GUI with a tree of the PR files
• A diff based on Monaco Editor (side by side view or unified)
• Ability to view/add comments on the files
• Approve / Reject / Comment buttons
• Previous diff / next diff buttons
• A viewed / not viewed status for each file (via localStorage)
• All in a single page, no page reload required, etc
• Dark theme

I'm planning to release it as open source when I think it's less buggy, but a few members of my team already use it (I do everyday).

Here is what it loooks like :

[zeripath]

Yes this is a known problem.

I know how to solve it but I still haven't been able to get round to it.

We need to make the diff page in sections and farm parts of it off to Ajax and other requests.

[typeless]

I have seen this issue too.
The bottleneck appears to be in the syntax highlight library.

I sampled the stack trace when my Gitea was hanging on showing pull diffs and got the following:

goroutine 396662 [runnable]:
github.com/danwakefield/fnmatch.Match(0x2a0e726, 0x4, 0xc012b7b520, 0x17, 0x0, 0xc00c773900)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/danwakefield/fnmatch/fnmatch.go:39 +0x78c
github.com/danwakefield/fnmatch.Match(0x2a0e726, 0x4, 0xc012b7b51d, 0x1a, 0x0, 0xc00c773900)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/danwakefield/fnmatch/fnmatch.go:108 +0x33f
github.com/alecthomas/chroma/lexers/internal.Match(0xc012b7b51d, 0x1a, 0xc012b7b535, 0x2)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/alecthomas/chroma/lexers/internal/api.go:94 +0x4fb
github.com/alecthomas/chroma/lexers.Match(...)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/alecthomas/chroma/lexers/lexers.go:51
code.gitea.io/gitea/modules/highlight.Code(0xc012b7b4a3, 0x94, 0xc014ce4781, 0x70, 0xc00b045a50, 0x40f13b)
	/home/mural/src/code.gitea.io/gitea/modules/highlight/highlight.go:77 +0x5af
code.gitea.io/gitea/services/gitdiff.(*DiffSection).GetComputedInlineDiffFor(0xc0131ed100, 0xc01349a140, 0x0, 0x0)
	/home/mural/src/code.gitea.io/gitea/services/gitdiff/gitdiff.go:551 +0x64c
reflect.Value.call(0x26a21e0, 0xc0131ed100, 0x213, 0x2a04a2d, 0x4, 0xc00c777578, 0x1, 0x1, 0xc013477cd8, 0x196, ...)
	/home/mural/src/golang.org/go1.16.3/src/reflect/value.go:476 +0x8e7
reflect.Value.Call(0x26a21e0, 0xc0131ed100, 0x213, 0xc00c777578, 0x1, 0x1, 0xc015ac5400, 0x27ae020, 0xc013477cd8)
	/home/mural/src/golang.org/go1.16.3/src/reflect/value.go:337 +0xb9
text/template.safeCall(0x26a21e0, 0xc0131ed100, 0x213, 0xc00c777578, 0x1, 0x1, 0x0, 0x0, 0x0, 0x0, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/funcs.go:365 +0xbd
text/template.(*state).evalCall(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x26a21e0, 0xc0131ed100, 0x213, 0x3f94dd0, 0xc00b227050, 0xc005f94969, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:725 +0x689
text/template.(*state).evalField(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0xc005f94969, 0x18, 0x3f94dd0, 0xc00b227050, 0xc0084472a0, 0x2, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:609 +0xbf1
text/template.(*state).evalFieldChain(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x26a21e0, 0xc013313400, 0x196, 0x3f94dd0, 0xc00b227050, 0xc008447290, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:570 +0x225
text/template.(*state).evalVariableNode(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0xc00b227050, 0xc0084472a0, 0x2, 0x2, 0x2698d20, 0x56a2da8, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:558 +0x2cc
text/template.(*state).evalCommand(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0xc00b226ff0, 0x2698d20, 0x56a2da8, 0x99, 0xc00b046ec8, 0x6, ...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:473 +0x825
text/template.(*state).evalPipeline(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0xc00ae9bec0, 0x0, 0x0, 0x0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:436 +0x125
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f948c0, 0xc00b2270b0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:255 +0x38a
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f94b90, 0xc00b226270)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b046ec8, 0xa, 0x27ae020, 0xc013477cd8, 0x196, 0xc00b1ff8c0, 0xc00b5b49f0, 0xc00b226270)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f94b48, 0xc00981e880)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f94b90, 0xc00b45c7b0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b046ec8, 0xa, 0x27ae020, 0xc013477cd8, 0x196, 0xc00b1fe9c0, 0xc00b45c7b0, 0x0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:294 +0x206
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f94b48, 0xc00981eb00)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b046ec8, 0x27ae020, 0xc013477cd8, 0x196, 0x3f94b90, 0xc00b45c5d0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkRange.func1(0x25a3b40, 0xc00c76f3b8, 0x82, 0x27ae020, 0xc013477cd8, 0x196)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:351 +0x125
text/template.(*state).walkRange(0xc00b046ec8, 0x26a21e0, 0xc013313400, 0x196, 0xc00981eb80)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:360 +0x2f8
text/template.(*state).walk(0xc00b046ec8, 0x26a21e0, 0xc013313400, 0x196, 0x3f94cb0, 0xc00981eb80)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:267 +0x445
text/template.(*state).walk(0xc00b046ec8, 0x26a21e0, 0xc013313400, 0x196, 0x3f94b90, 0xc00b45c480)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkRange.func1(0x25a3b40, 0x54e4740, 0x82, 0x26a21e0, 0xc013313400, 0x196)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:351 +0x125
text/template.(*state).walkRange(0xc00b046ec8, 0x267f400, 0xc017687098, 0x95, 0xc00981ec00)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:360 +0x2f8
text/template.(*state).walk(0xc00b046ec8, 0x267f400, 0xc017687098, 0x95, 0x3f94cb0, 0xc00981ec00)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:267 +0x445
text/template.(*state).walk(0xc00b046ec8, 0x267f400, 0xc017687098, 0x95, 0x3f94b90, 0xc00b45c270)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkTemplate(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0xc00515cc40)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:418 +0x225
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94d40, 0xc00515cc40)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:269 +0x205
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b90, 0xc01e97e450)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b047a50, 0xa, 0x26a2160, 0xc0138f9d80, 0x196, 0xc00a10f020, 0xc01e97e330, 0xc01e97e450)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b48, 0xc00515cd40)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b90, 0xc01e97e240)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b047a50, 0xa, 0x26a2160, 0xc0138f9d80, 0x196, 0xc00a10ef60, 0xc01e97e0c0, 0xc01e97e240)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b48, 0xc00515ce40)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b90, 0xc00d9a32f0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b047a50, 0xa, 0x26a2160, 0xc0138f9d80, 0x196, 0xc009e47980, 0xc006632e40, 0xc00d9a32f0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b48, 0xc004fafc80)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b047a50, 0x26a2160, 0xc0138f9d80, 0x196, 0x3f94b90, 0xc006632d50)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkRange.func1(0x25a3b40, 0x54e48c0, 0x82, 0x26a2160, 0xc0138f9d80, 0x196)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:351 +0x125
text/template.(*state).walkRange(0xc00b047a50, 0x267f400, 0xc00e1d6e70, 0x15, 0xc004fafd00)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:360 +0x2f8
text/template.(*state).walk(0xc00b047a50, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94cb0, 0xc004fafd00)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:267 +0x445
text/template.(*state).walk(0xc00b047a50, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc009373dd0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b047a50, 0xa, 0x267f400, 0xc00e1d6e70, 0x15, 0xc009e47080, 0xc009373860, 0xc009373dd0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b047a50, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b48, 0xc006bc6440)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b047a50, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc0093737d0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkTemplate(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0xc00caed680)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:418 +0x225
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94d40, 0xc00caed680)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:269 +0x205
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc00c0465a0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b048168, 0xa, 0x267f400, 0xc00e1d6e70, 0x15, 0xc00c0390e0, 0xc00c0462d0, 0xc00c0465a0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b48, 0xc00caed6c0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc00c046210)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b048168, 0xa, 0x267f400, 0xc00e1d6e70, 0x15, 0xc00c038fc0, 0xc00c046210, 0xc00c101c80)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:294 +0x206
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b48, 0xc00caed8c0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc00c0460c0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*state).walkIfOrWith(0xc00b048168, 0xa, 0x267f400, 0xc00e1d6e70, 0x15, 0xc00c088a20, 0xc00c08ab40, 0xc00c0460c0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:297 +0x265
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b48, 0xc00caed900)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:261 +0x285
text/template.(*state).walk(0xc00b048168, 0x267f400, 0xc00e1d6e70, 0x15, 0x3f94b90, 0xc00c020f30)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:264 +0x13c
text/template.(*Template).execute(0xc00c9c67c0, 0x3f52860, 0xc00f0e22a0, 0x267f400, 0xc00e1d6e70, 0x0, 0x0)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:220 +0x1c6
text/template.(*Template).Execute(...)
	/home/mural/src/golang.org/go1.16.3/src/text/template/exec.go:203
html/template.(*Template).ExecuteTemplate(0xc0067ce450, 0x3f52860, 0xc00f0e22a0, 0x2b227cb, 0x11, 0x267f400, 0xc00e1d6e70, 0x18, 0xc00bbd8bd0)
	/home/mural/src/golang.org/go1.16.3/src/html/template/template.go:139 +0xab
github.com/unrolled/render.HTML.Render(0xc00bbd8bd0, 0x18, 0xc8, 0x2b227cb, 0x11, 0xc0067ce450, 0x3f70af8, 0xc005d11ce0, 0x7fa1b77475f0, 0xc00e17ba80, ...)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/unrolled/render/engine.go:94 +0xb1
github.com/unrolled/render.(*Render).Render(0xc004722f00, 0x7fa1b77475f0, 0xc00e17ba80, 0x3f59340, 0xc00ce2d940, 0x267f400, 0xc00e1d6e70, 0x0, 0x0)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/unrolled/render/render.go:377 +0x6c
github.com/unrolled/render.(*Render).HTML(0xc004722f00, 0x7fa1b77475f0, 0xc00e17ba80, 0xc8, 0x2b227cb, 0x11, 0x267f400, 0xc00e1d6e70, 0x0, 0x0, ...)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/unrolled/render/render.go:433 +0x325
code.gitea.io/gitea/modules/context.(*Context).HTML(0xc01fa77200, 0xc8, 0x2b227cb, 0x11)
	/home/mural/src/code.gitea.io/gitea/modules/context/context.go:189 +0x270
code.gitea.io/gitea/routers/repo.CompareDiff(0xc01fa77200)
	/home/mural/src/code.gitea.io/gitea/routers/repo/compare.go:677 +0xd70
code.gitea.io/gitea/modules/web.Wrap.func1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/modules/web/route.go:64 +0x1dc
net/http.HandlerFunc.ServeHTTP(0xc007858e80, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
github.com/go-chi/chi.(*Mux).routeHTTP(0xc007844d80, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:436 +0x28b
net/http.HandlerFunc.ServeHTTP(0xc00755df00, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/modules/web.Middle.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/modules/web/route.go:103 +0x137
net/http.HandlerFunc.ServeHTTP(0xc0078427c0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/modules/web.Middle.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/modules/web/route.go:103 +0x137
net/http.HandlerFunc.ServeHTTP(0xc0078427e0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/modules/web.Middle.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/modules/web/route.go:103 +0x137
net/http.HandlerFunc.ServeHTTP(0xc007842800, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
github.com/go-chi/chi/middleware.GetHead.func1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/middleware/get_head.go:37 +0x182
net/http.HandlerFunc.ServeHTTP(0xc003c41248, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4700)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/modules/context.Contexter.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/code.gitea.io/gitea/modules/context/context.go:751 +0x1dca
net/http.HandlerFunc.ServeHTTP(0xc0078474a0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
github.com/go-chi/chi.(*Mux).ServeHTTP(0xc007844d80, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:70 +0x5ab
github.com/go-chi/chi.(*Mux).Mount.func1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:311 +0x17c
net/http.HandlerFunc.ServeHTTP(0xc0078dfd40, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
github.com/go-chi/chi.(*Mux).routeHTTP(0xc004728f00, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:436 +0x28b
net/http.HandlerFunc.ServeHTTP(0xc005c8db90, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/routers/routes.Recovery.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/code.gitea.io/gitea/routers/routes/base.go:211 +0x91
net/http.HandlerFunc.ServeHTTP(0xc005ca92c0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4600)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
gitea.com/go-chi/session.Sessioner.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/code.gitea.io/gitea/vendor/gitea.com/go-chi/session/session.go:256 +0x24f
net/http.HandlerFunc.ServeHTTP(0xc005ca92e0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
code.gitea.io/gitea/modules/public.AssetsHandler.func1.1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/code.gitea.io/gitea/modules/public/public.go:42 +0x8f
net/http.HandlerFunc.ServeHTTP(0xc005cd0ab0, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
github.com/go-chi/chi.(*Mux).ServeHTTP(0xc004728f00, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:70 +0x5ab
github.com/go-chi/chi.(*Mux).Mount.func1(0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/code.gitea.io/gitea/vendor/github.com/go-chi/chi/mux.go:311 +0x17c
net/http.HandlerFunc.ServeHTTP(0xc0078dfd60, 0x3f78d28, 0xc00e17ba80, 0xc00e1d4500)
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:2069 +0x44
created by net/http.(*Server).Serve
	/home/mural/src/golang.org/go1.16.3/src/net/http/server.go:3013 +0x39b

[typeless]

Looking at https://github.com/alecthomas/chroma/blob/7e282be4957c2cb4edeb4562f56d707427393192/lexers/internal/api.go#L91-L98, I am afraid it's noticeably expensive to search for a lexer for every line of code.

See also

gitea/services/gitdiff/gitdiff.go

Line 551 in f4d3bf7

return template.HTML(highlight.Code(diffSection.FileName, diffLine.Content[1:]))

[typeless]

Infinite scrolling pagination (https://www.digitalocean.com/community/tutorials/vuejs-implementing-infinite-scroll) might be a relatively simple way to address this if it doesn't require redesigning the UI.

[zeripath]

Looking at https://github.com/alecthomas/chroma/blob/7e282be4957c2cb4edeb4562f56d707427393192/lexers/internal/api.go#L91-L98, I am afraid it's noticeably expensive to search for a lexer for every line of code.

I guess that shows where we can seriously improve then...

The lexer detection should be run on the old file and run on the new file once and then reused.

[typeless]

@zeripath
#16180 helps to some extent, yet it's still suboptimal.
For the record, I have a PR that translates into 40MB of HTML and takes 10mins to generate (73 added files, btw). It seems to be stuck in html/template forever. Given the scenario, I think AJAX would probably make more difference in fixing this problem.