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Title: System memory cache is consistently at zero
Post by: camellia on July 10, 2026, 12:02:33 AM

Hi everyone

System memory cache in "Reporting Health" is always zero.

Reporting_Health_System_memory.png

Should the graph show "laundry" instead of "cache"?
Is the graph always zero because it doesn't reflect the value of "laundry"?

Title: Re: System memory cache is consistently at zero
Post by: Patrick M. Hausen on July 10, 2026, 08:57:56 AM

Are you running ZFS? ZFS ARC (adaptive replacement cache) is shown as wired, not cache. Only traditional UFS buffer cache woukd ever show up as cache.

Title: Re: System memory cache is consistently at zero
Post by: camellia on July 10, 2026, 09:04:53 PM

I am running UFS.

It appears that the "cache" metric no longer exists in the memory line of the top command. "Laundry" exists in place of "cache," and it shows a non-zero value.

If the "System memory" in "Reporting Health" follows the memory metrics used by the top command, I believe it would be better to eliminate "cache" and introduce "laundry."

Is it not possible to change the cache display, given the need to maintain compatibility with past data?

Title: Re: System memory cache is consistently at zero
Post by: nero355 on July 11, 2026, 03:10:24 AM

Quote from: camellia on July 10, 2026, 09:04:53 PMIt appears that the "cache" metric no longer exists in the memory line of the top command. "Laundry" exists in place of "cache," and it shows a non-zero value.

If the "System memory" in "Reporting Health" follows the memory metrics used by the top command, I believe it would be better to eliminate "cache" and introduce "laundry."

If you are adventurous you could edit it in the source code of the component(s) responsible for the function :)

Title: Re: System memory cache is consistently at zero
Post by: sopex on July 16, 2026, 04:35:53 PM

Quote from: camellia on July 10, 2026, 09:04:53 PMI am running UFS.

It appears that the "cache" metric no longer exists in the memory line of the top command. "Laundry" exists in place of "cache," and it shows a non-zero value.

If the "System memory" in "Reporting Health" follows the memory metrics used by the top command, I believe it would be better to eliminate "cache" and introduce "laundry."

Is it not possible to change the cache display, given the need to maintain compatibility with past data?

In case you want to try it: opnsense-core -a sopex 5bfd77c

Otherwise it will be in some following release.
https://github.com/opnsense/core/commit/5bfd77cff2fcaf995db88cc5d4bef1eb070c95d7

Title: Re: System memory cache is consistently at zero
Post by: camellia on July 20, 2026, 02:37:27 PM

Quote from: sopex on July 16, 2026, 04:35:53 PMIn case you want to try it: opnsense-core -a sopex 5bfd77c

Reporting_Health_System_memory_patch.png

Cache is back!

Thanks.

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English Forums => General Discussion => Topic started by: camellia on July 10, 2026, 12:02:33 AM