Do not pass -jN to make, use cargo jobserver instead

[tmpolaczyk]

When compiling a crate that has jemallocator-sys as a dependency with cargo build -j4, I see a short spike where the number of cpu cores used is 8 instead of 4. The cause is this crate using the NUM_JOBS env var to call make, which ignores that cargo already has other running jobs, thus bringing the total number of running jobs to be higher than NUM_JOBS. This doesn't happen in any of the other *-sys crates, I guess because they use the cc crate with the parallel feature enabled instead of manually calling make.

The fix is to remove the -jN arg to make if the CARGO_MAKEFLAGS env var exists, and set MAKEFLAGS to CARGO_MAKEFLAGS instead.

I expect the implementation to be similar to this:

https://github.com/rust-lang/cmake-rs/blob/c4a60dd154dd90e469dffc41a1faa717704f90b3/src/lib.rs#L830

I guess using a crate to call make instead of doing it manually would handle this and other issues automatically, but I don't know what's the standard so I can't recommend any crates.

[BusyJay]

The fix is to remove the -jN arg to make if the CARGO_MAKEFLAGS env var exists, and set MAKEFLAGS to CARGO_MAKEFLAGS instead.

Make sense. Would you like to send a PR?

[tmpolaczyk]

I tried to run cargo build but it gave me a strange error "configure: error: cannot find sources (Makefile.in)", and I didn't find any documentation on what should I do to fix it, so I will let some other contributor implement it.

[BusyJay]

Likely the same problem as https://github.com/tikv/jemallocator/issues/32.

[reneleonhardt]

@tmpolaczyk Were you able to clone the submodules, do you still want to contribute a PR? 🙂

[tmpolaczyk]

Hi, I gave up, and in general this doesn't sound like an easy issue so anyone else feel free to take it

[reneleonhardt]

No problem, thank you for reporting!

[reneleonhardt]

I created a pull request.

Old logic:

• CARGO_MAKEFLAGS is empty -> make -jN
• CARGO_MAKEFLAGS is set -> concatenate or set MAKEFLAGS

New logic:

• CARGO_MAKEFLAGS is set -> concatenate or set MAKEFLAGS
• MAKEFLAGS is set -> use MAKEFLAGS unchanged
• Otherwise -> make -jN

[goffrie]

I believe this was fixed by #120.

[eitsupi]

I saw something like this in conda-forge/staged-recipes#31488:

 │ │   running: cd "$SRC_DIR/src/rust/target/x86_64-unknown-linux-gnu/release/build/tikv-jemalloc-sys-cde55cd13423d9e3/out/build" && MAKEFLAGS=" -- OBJECTS=init.o SHLIB=polars.so -j --jobserver-fds=8,9 --jobserver-auth=8,9" "make"
 │ │   make[1]: Entering directory '$SRC_DIR/src/rust/target/x86_64-unknown-linux-gnu/release/build/tikv-jemalloc-sys-cde55cd13423d9e3/out/build'
 │ │   make[1]: Leaving directory '$SRC_DIR/src/rust/target/x86_64-unknown-linux-gnu/release/build/tikv-jemalloc-sys-cde55cd13423d9e3/out/build'
 │ │   --- stderr
 │ │   make[1]: *** No rule to make target '-j'.  Stop.
 │ │   thread 'main' (6599) panicked at $BUILD_PREFIX/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tikv-jemalloc-sys-0.6.1+5.3.0-1-ge13ca993e8ccb9ba9847cc330696e02839f328f7/build.rs:411:9:
 │ │   command did not execute successfully: cd "$SRC_DIR/src/rust/target/x86_64-unknown-linux-gnu/release/build/tikv-jemalloc-sys-cde55cd13423d9e3/out/build" && MAKEFLAGS=" -- OBJECTS=init.o SHLIB=polars.so -j --jobserver-fds=8,9 --jobserver-auth=8,9" "make"

It seems like there might be something wrong with the current state.

[Kobzol]

Hi, could you please clarify what sort of make you are using? Cargo normally passes -j --jobserver-fds= --jobserver-auth=, and it seems to work for GNU Make for me. I also looked online and it seems that it is the expected usage.

[eitsupi]

Hi, could you please clarify what sort of make you are using?

This was confirmed on conda-forge CI, the logs are here. https://dev.azure.com/conda-forge/feedstock-builds/_build/results?buildId=1392965&view=logs&j=4cabe686-70ae-553a-7fd0-310379f2cbac&t=6a4fc7c9-c31a-5115-eff9-6479d72b69ff

It says:

 │ │ │ make                              ┆ 4.4.1              ┆ hb9d3cd8_2   ┆ conda-forge ┆  501.06 KiB │

https://dev.azure.com/conda-forge/feedstock-builds/_build/results?buildId=1392965&view=logs&j=4cabe686-70ae-553a-7fd0-310379f2cbac&t=6a4fc7c9-c31a-5115-eff9-6479d72b69ff&l=783

Seems from: https://github.com/conda-forge/make-feedstock

[BusyJay]

MAKEFLAGS=" -- OBJECTS=init.o SHLIB=polars.so -j --jobserver-fds=8,9 --jobserver-auth=8,9" "make"

The problem may come from --, which requires argument for flags, and -j has no aurgument, so it will be parsed as a target instead of flags.

[Kobzol]

Hmm, for my make 4.3, it works even with -- for me. Maybe we could reverse the order here and add the Cargo makeflags at the beginning (not the end) of any existing makeflags?

[BusyJay]

LGTM, in worse case, job sever is overridden by user provided flags, which seems OK.

[Kobzol]

Ok, https://github.com/tikv/jemallocator/pull/152.