Memory leak on Raspberrypi Zero W

[tiny-tinker]

• SerialPort Version: 6.2.0

• NodeJS Version: v6.11.4 also v8.11.1

• Operating System and Hardware Platform: Raspbian GNU/Linux 9.3 (stretch)

• Have you checked the right version of the api docs?: Yes

• Are you having trouble installing and you checked the Installation Special Cases docs? No issues installing

• Are you using Electron and have you checked the Electron Docs?: N/A

Summary of Problem

I am getting a memory leak of about 2MB per second and CPU thrashing.

Steps and Code to Reproduce the Issue

var SerialPort = require('serialport');
var port = new SerialPort('/dev/ttyAMA0', {
  baudRate: 115200
});


// Switches the port into "flowing mode"
port.on('data', function (data) {
  console.log('Data:', data.toString() );
});

I thought it might be #1572 so I waited for the fix there, but I still have the issue using 6.2.0 . The weird thing is that I don't have the memory leak on a raspberry pi zero (no wifi). Other assorted details:

root@raspberrypi:# node -v
v6.11.4 
root@raspberrypi:# grep serialport package.json 
    "serialport": "^6.2.0",
root@raspberrypi:~# lsb_release -a
No LSB modules are available.
Distributor ID: Raspbian
Description:    Raspbian GNU/Linux 9.3 (stretch)
Release:    9.3
Codename:   stretch
root@raspberrypi:~# cat /boot/cmdline.txt
dwc_otg.lpm_enable=0 console=tty1 root=PARTUUID=74121984-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash

I'm guessing it is environment related, but not sure where to look.

[shodan8192]

Confirmed on :

RPi Zero W v1.1
NodeJS : v8.11.3
Raspbian 9.4 (stretch)

rss usage grow by ~2MB/s and cpu load is almost 100%

Cause

On RPi Zero W (and probably RPi 3) port serial1 is linked to ttyAMA0 and used by Bluetooth

pi@zero:~ $ ls -la /dev/ttyAMA0
lrwxrwxrwx 1 root root 7 Jun 25 13:53 /dev/serial1 -> ttyAMA0

pi@zero:~ $ systemctl status hciuart.service -l
● hciuart.service - Configure Bluetooth Modems connected by UART
   Loaded: loaded (/lib/systemd/system/hciuart.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2018-06-25 13:53:17 CEST; 17s ago
  Process: 227 ExecStart=/usr/bin/btuart (code=exited, status=0/SUCCESS)
 Main PID: 357 (hciattach)
   CGroup: /system.slice/hciuart.service
           └─357 /usr/bin/hciattach /dev/serial1 bcm43xx 3000000 flow - b8:27:eb:35:a6:a0

Solution 1

Don't use /dev/serial1 or /dev/ttyAMA0.
Instead, add enable_uart=1 to /boot/config.txt and reboot.

Device /dev/serial0 will appear. It is wired to GPIO14 and 15.
This serial port is miniUART and have serious limitations (as one can find in net)

Solution 2 (maybe better)

If Bluetooth is not needed, add dtoverlay=pi3-disable-bt to /boot/config.txt and reboot. Now full UART /dev/ttyAMA0 is usable on GPIO14 and 15.

[xMTinkerer]

Woo! This did it:

If Bluetooth is not needed, add dtoverlay=pi3-disable-bt to /boot/config.txt and reboot. Now full UART /dev/ttyAMA0 is usable on GPIO14 and 15.

Thanks!

[reconbot]

Nice!