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  • Use KillMode=process with caution: restart loop could deplete resources

    calendar Dec 12, 2025 · 4 min read · Linux systemd  ·
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    I recently debugged a resource leak where a systemd service kept restarting while leaving a process behind after each restart. The root cause isn't particularly interesting: a backward-incompatible third-party dependency upgrade. But the debugging process and lessons learned are. Thousands of zombie processes from a …


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  • Spawning a New Process for Socket-Activated Daemons is Error-Prone

    calendar Dec 10, 2025 · 4 min read · Linux systemd Container  ·
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    I recently debugged a mysterious latency issue: after migrating a systemd service from path-activation to socket-activation, there was a consistent ~1 second time-to-available latency. The culprit was a bad practice—starting the daemon program as a new process in socket-activation. Let's dive into the details. Starting …


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Peng Zhang

Software Engineer

Recent Posts

  • Simplify device path on boot with udev
  • Use KillMode=process with caution: restart loop could deplete resources
  • Spawning a New Process for Socket-Activated Daemons is Error-Prone
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