Great, exactly what I was looking for, thanks! For some reason I wasn't able to find this. On 9/3/22 16:34, Brandon Allbery wrote:

There is `-ddump-timings`.

On Sat, Sep 3, 2022 at 10:31 AM rowan goemans wrote:

...

Dear Cafe,

I have a Haskell Project where I have a module that quite heavily makes use of constraints and takes ages to compile per module. It also uses some type checker plugins but I'm unsure if they are causing the slowness. So what I would like to see is a breakdown of how much time GHC is spending on compilation of a module. Does something like this exist?

Best regards,

Rowan Goemans

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Hi Hécate, Thank you this helps a lot. I now at least have confirmed my suspicion that it's the type checker. It spends a whopping 50 seconds in there for a module not even 300 lines of code. Is there someway to analyze the type checker specifically? I know there is tc-trace but that doesn't really tell me what is taking long. Best regards, Rowan Goemans On 9/3/22 20:21, Hécate wrote:

Hi Rowan,

I had a nice experience using https://github.com/codedownio/time-ghc-modules. Do tell us if this fits your needs. :)

Cheers, Hécate

Le 3 septembre 2022 16:31:35 rowan goemans a écrit :

...

Dear Cafe,

I have a Haskell Project where I have a module that quite heavily makes use of constraints and takes ages to compile per module. It also uses some type checker plugins but I'm unsure if they are causing the slowness. So what I would like to see is a breakdown of how much time GHC is spending on compilation of a module. Does something like this exist?

Best regards,

Rowan Goemans

_______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.

You may want to take a look at this talk https://www.youtube.com/watch?v=ABScdJqy5wg by Edsko. It talks about several cases where the compile time may blow up quadratically depending on the size of the structure. Your problem might be something similar. Also see https://hackage.haskell.org/package/large-records . -harendra On Sun, 4 Sept 2022 at 02:26, rowan goemans wrote:

Hi Hécate,

Thank you this helps a lot. I now at least have confirmed my suspicion that it's the type checker. It spends a whopping 50 seconds in there for a module not even 300 lines of code. Is there someway to analyze the type checker specifically? I know there is tc-trace but that doesn't really tell me what is taking long.

Best regards,

Rowan Goemans

On 9/3/22 20:21, Hécate wrote:

Hi Rowan,

I had a nice experience using https://github.com/codedownio/time-ghc-modules. Do tell us if this fits your needs. :)

Cheers, Hécate

Le 3 septembre 2022 16:31:35 rowan goemans a écrit :

...

Dear Cafe,

I have a Haskell Project where I have a module that quite heavily makes use of constraints and takes ages to compile per module. It also uses some type checker plugins but I'm unsure if they are causing the slowness. So what I would like to see is a breakdown of how much time GHC is spending on compilation of a module. Does something like this exist?

Best regards,

Rowan Goemans

_______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.

_______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.