Lucas Manuel Rodriguez
3e4cf63d31
Resolves #46461. - [X] Changes file added for user-visible changes in `changes/`, `orbit/changes/` or `ee/fleetd-chrome/changes`. --- Verification command (checks how many times /proc/stat is read): ``` sudo bpftrace -e ' tracepoint:syscalls:sys_enter_openat /str(args->filename) == "/proc/stat" || str(args->filename) == "/proc/uptime"/ { @[comm, str(args->filename)] = count(); } interval:s:60 { exit(); }' ``` 1.57.0 outputs: ``` @[orbit, /proc/stat]: 1084 ``` fleetd built with changes in this PR (and I had to trigger a restart, otherwise it's 0): ``` @[orbit, /proc/stat]: 3 [...] @[fleet-desktop, /proc/stat]: 6 ``` ## Testing - [X] QA'd all new/changed functionality manually ## fleetd/orbit/Fleet Desktop - [x] Verified compatibility with the latest released version of Fleet (see [Must rule](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/workflows/fleetd-development-and-release-strategy.md)) - [X] If the change applies to only one platform, confirmed that `runtime.GOOS` is used as needed to isolate changes - [X] Verified that fleetd runs on macOS, Linux and Windows - [X] Verified auto-update works from the released version of component to the new version (see [tools/tuf/test](../tools/tuf/test/README.md)) <!-- This is an auto-generated comment: release notes by coderabbit.ai --> ## Summary by CodeRabbit * **Bug Fixes** * Improved process listing performance on Linux by reducing repeated system boot-time reads. * Prevented unnecessary refreshes during frequent process checks, helping watchdog-style polling run more efficiently. <!-- end of auto-generated comment: release notes by coderabbit.ai -->
36 lines
1.5 KiB
Go
36 lines
1.5 KiB
Go
//go:build linux
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package platform
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import (
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gopsutil_process "github.com/shirou/gopsutil/v4/process"
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)
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func init() {
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// Enable gopsutil's boot-time cache (Linux only).
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//
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// gopsutil_process.Processes() builds a Process for every PID, and the
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// constructor (NewProcess -> CreateTime -> fillFromStat) computes each
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// process' creation time, which requires the system boot time. By default
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// gopsutil does NOT cache the boot time, so on Linux it re-reads /proc/stat
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// (or /proc/uptime on containerized hosts) once per process, on every call.
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//
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// orbit enumerates the full process table on a recurring basis (e.g. the
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// Fleet Desktop watchdog polls every 15s via GetProcessesByName), so this
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// caused the host-wide /proc/stat file to be read N times per poll, where N
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// is the total number of running processes. The btime field lives near the
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// end of /proc/stat, so each read scans the entire file just to recover a
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// single constant value.
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//
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// The system boot time does not change for the lifetime of the orbit
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// process, so caching it is safe and collapses those repeated reads into a
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// single one. This is scoped to Linux because that is where the redundant
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// file reads occur; macOS and Windows obtain boot time via syscall/sysctl.
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//
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// Note: orbit only reads process Name/Pid and never a process' CreateTime,
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// so the cache cannot surface a stale value (the gopsutil README warns that
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// a cached boot time can drift if NTP steps the clock after boot, which only
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// affects CreateTime).
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gopsutil_process.EnableBootTimeCache(true)
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}
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