deno v1.4.5 use 100% of CPU if it start an HTTP server

[jersou]

With deno 1.4.5, I have 100% CPU usage with all scripts that use an HTTP server, I don't have these problems with 1.4.4:

$ ./deno-1.4.4 --version                                                                                                                                       
      deno 1.4.4
      v8 8.7.75
      typescript 4.0.3
$ ./deno-1.4.5 --version
      deno 1.4.5
      v8 8.7.220.3
      typescript 4.0.3
$ ./deno-1.4.4  run --allow-net https://deno.land/[email protected]/examples/echo_server.ts & sleep 10 && ps -p "$(pgrep deno)" -o %cpu,%mem,cmd && pkill deno        
      [1] 43965
      Listening on 0.0.0.0:8080
      %CPU %MEM CMD
       0.0  0.0 ./deno-1.4.4 run --allow-net https://deno.land/[email protected]/examples/echo_server.ts
      [1]  + 43965 terminated  ./deno-1.4.4 run --allow-net                                                                                                                               
$ ./deno-1.4.5  run --allow-net https://deno.land/[email protected]/examples/echo_server.ts & sleep 10 && ps -p "$(pgrep deno)" -o %cpu,%mem,cmd && pkill deno
      [1] 44519
      Check https://deno.land/[email protected]/examples/echo_server.ts
      Listening on 0.0.0.0:8080
      %CPU %MEM CMD
      102  0.1 ./deno-1.4.5 run --allow-net https://deno.land/[email protected]/examples/echo_server.ts
      [1]  + 44519 terminated  ./deno-1.4.5 run --allow-net

My OS : Ubuntu 20.04.1 LTS

[jersou]

To be sure, I tried it from docker containers :

The Dockerfile :

# FROM https://github.com/hayd/deno-docker/blob/master/alpine.dockerfile
FROM frolvlad/alpine-glibc:alpine-3.11_glibc-2.31
RUN addgroup -g 1993 -S deno \
        && adduser -u 1993 -S deno -G deno \
        && mkdir /deno-dir/ \
        && chown deno:deno /deno-dir/
ENV DENO_DIR /deno-dir/
ENV DENO_INSTALL_ROOT /usr/local
ARG DENO_VERSION
RUN apk add --virtual .download --no-cache curl \
        && curl -fsSL https://github.com/denoland/deno/releases/download/v${DENO_VERSION}/deno-x86_64-unknown-linux-gnu.zip \
        --output deno.zip \
        && unzip deno.zip \
        && rm deno.zip \
        && chmod 777 deno \
        && mv deno /bin/deno \
        && apk del .download
CMD ["deno", "run", "--allow-net", "https://deno.land/[email protected]/examples/echo_server.ts"]

Build and run the 2 versions :

$ docker build -t deno-1.4.4 --build-arg DENO_VERSION=1.4.4 .
$ docker build -t deno-1.4.5 --build-arg DENO_VERSION=1.4.5 .
$ docker run -d --rm --init --name deno-1.4.4 deno-1.4.4 && docker run -d --rm --init --name deno-1.4.5 deno-1.4.5 && sleep 10 && docker stats --no-stream && docker kill deno-1.4.4 deno-1.4.5
33c6ab5a5c3abdea4427f337c7ffdce31e54817fef8956286986055fb30e9496
6bdbd15ef0fed716349dd6a316d02e76eac84087c063d805600c3bc1199f3d33
CONTAINER ID        NAME                CPU %               MEM USAGE / LIMIT     MEM %               NET I/O             BLOCK I/O           PIDS
6bdbd15ef0fe        deno-1.4.5          99.28%              30.59MiB / 31.21GiB   0.10%               7.93kB / 1.33kB     0B / 0B             9
33c6ab5a5c3a        deno-1.4.4          0.00%               27.63MiB / 31.21GiB   0.09%               8.23kB / 1.33kB     0B / 0B             9
deno-1.4.4

$ uname -a 
Linux jer 5.4.0-48-generic #52-Ubuntu SMP Thu Sep 10 10:58:49 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

[jersou]

There is no relation to HTTP server finally, I have the same bug with catj example and others :

$ (sleep 10 && ps -p "$(pgrep deno)" -o %cpu,%mem,cmd && pkill deno) & ./deno-1.4.5 eval 'import { sleep } from "https://deno.land/x/sleep/mod.ts"; await sleep(100)'
%CPU %MEM CMD
 102  0.1 ./deno-1.4.5 eval import { sleep } from "https://deno.land/x/sleep/mod.ts"; await sleep(100)

$ (sleep 10 && ps -p "$(pgrep deno)" -o %cpu,%mem,cmd && pkill deno) & ./deno-1.4.5 run https://deno.land/[email protected]/examples/catj.ts -
%CPU %MEM CMD
 100  0.0 ./deno-1.4.5 run https://deno.land/[email protected]/examples/catj.ts -

$ (sleep 10 && ps -p "$(pgrep deno)" -o %cpu,%mem,cmd && pkill deno) & ./deno-1.4.5 eval 'new Promise(r => setTimeout(r, 100000))'
%CPU %MEM CMD
 0.1  0.0 ./deno-1.4.5 eval new Promise(r => setTimeout(r, 100000))

It's a strange bug, I guess deno doesn't have this behavior on all machines.
Edit: My Windows 7 VM have the same bug :

[ry]

@jersou Thanks for the report - this is indeed a major oversight. I have a fix and we will make a new release tomorrow.