Re: bin/60607: /etc/rc does too much throw-away work and is needlessly slow on constrained systems
"Jason Thorpe via gnats" <[email protected]>
| Newsgroups | gmane.os.netbsd.bugs |
|---|---|
| Message-ID | <[email protected]> |
The following reply was made to PR bin/60607; it has been noted by GNATS. From: Jason Thorpe <[email protected]> To: Taylor R Campbell <[email protected]> Cc: "[email protected]" <[email protected]>, "[email protected]" <[email protected]> Subject: Re: bin/60607: /etc/rc does too much throw-away work and is needlessly slow on constrained systems Date: Mon, 17 Aug 2026 18:28:57 -0700 > On Aug 17, 2026, at 6:42=E2=80=AFAM, Jason Thorpe <[email protected]> = wrote: >=20 > The cache can=E2=80=99t live on /var because /var might not be = available when the cache is required (this would especially be the case = for read-only roots). The only path that=E2=80=99s currently guaranteed = to be available when /etc/rc starts processing the rc.d scripts is /etc. = It=E2=80=99s pretty straightforward to suppress any error messages that = might occur when writing out the cache (which happens as the last step = of the boot process). And, yes, I can refactor the code that builds and = writes out the cache into rc.subr so that there can be a =E2=80=9Cnostart=E2= =80=9D rc.d script to rebuild it for those who wish to do that before = the next reboot. Updated patch: https://www.netbsd.org/~thorpej/rcorder-cache-diff-v2.txt Also ran it on my AlphaStation 200 4/233. Even with a few heavy hitters = in the boot of that machine (ntpd wiring itself, sshd, fontconfig cache, = IPv6 DAD, etc.) that consume most of the time, it still managed to save = 20 seconds, reducing =E2=80=9Cdate-to-date=E2=80=9D boot time from 2min = 20sec to 2min flat. -- thorpej