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+--- Thread: [IDEA] Moving caches to SDRAM (/showthread.php?tid=2862)
Moving caches to SDRAM - tinyreminder - 08-05-2020
Hello all,
It seems that moving cache files to SDRAM improve sound quality.
I wrote howto:
https://qiita.com/tinyreminder/items/cc10edf6a4cdf321ff51
I would like to know your impression.
Thanks in advance,
RE: Moving caches to SDRAM - philrandal - 08-05-2020
What uses
/home/pi/.cache
I'd be tempted to leave logging as it is, for forensic purposes after any OS crashes and reboots.
Does changing each of the tmp and .cache directories one at a time make an audible difference?
Which of those three is most effective, and does changing them all make a noticeable difference over just changing .cache?
Cheers,
Phil
RE: Moving caches to SDRAM - TheOldPresbyope - 08-05-2020
(08-05-2020, 05:52 AM)tinyreminder Wrote: Hello all,
It seems that moving cache files to SDRAM improve sound quality.
You lost me right there. Carl Sagan said it best "extraordinary claims require extraordinary evidence." [1]
Specifically, what improvement in sound quality is to be expected?
Ummm, let me see. I'm playing a track right now in a moOde 6.7.1 installation. There's not /home/pi/.cache in the file system and I don't see current time stamps on files in the other directories mentioned in your howto. Just to be sure, I installed lsof and I don't see any running process with an open file in those directories.
Color me skeptical.
Regards,
Kent
[1] well, actually, Carl said it best in English. The famous mathematician and proto-mathematical physicist Pierre-Simon Laplace said essentially the same thing in French 200 years earlier.
RE: Moving caches to SDRAM - Tim Curtis - 08-05-2020
/home/pi/.cache will be created after chromium-browser is started.
RE: Moving caches to SDRAM - TookaFace - 08-05-2020
You also can run moode on an overlay, that way the whole system will be sort of read only, and all changes will go on RAM.
U can easily do that with sudo raspi-config - advanced option - overlay FS
U also preserve SDcard lifetime that way, and no one can break ur installation since all changes are gone after a reboot.
RE: Moving caches to SDRAM - TheOldPresbyope - 08-05-2020
(08-05-2020, 02:55 PM)Tim Curtis Wrote: /home/pi/.cache will be created after chromium-browser is started.
Ah. of course.
OTOH, if R/W cycles to that directory are somehow implicated, it could be a problem only when the local display is in use. Has any moOde user ever remarked on experiencing a diminution in sound quality when they enable the local display?
Regards,
Kent
RE: Moving caches to SDRAM - tinyreminder - 08-06-2020
(08-05-2020, 12:55 PM)philrandal Wrote: What uses
/home/pi/.cache
I'd be tempted to leave logging as it is, for forensic purposes after any OS crashes and reboots.
Does changing each of the tmp and .cache directories one at a time make an audible difference?
Which of those three is most effective, and does changing them all make a noticeable difference over just changing .cache?
Cheers,
Phil
Sorry, the entry I wrote is bit old.
Moving /var/log to SDRAM causes lots of problem.
In my opnion, moving /var/cache to SDRAM causes difference.
To try, add the line
Code:
tmpfs /var/cache tmpfs defaults,size=500m,noatime 0 0Moving other tmp directories such as /tmp and /var/tmp to SDRAM seems not to cause difference
but I think it helps to improve SD card lifetime.
Regards,
Takeshi
RE: Moving caches to SDRAM - modeosonja - 08-21-2020
Thank you so much für your advice
RE: Moving caches to SDRAM - aknaggbaugh - 04-13-2021
I tried moving /var/cache to RAM and could hear no difference in audio quality on my system (Pi2Design 502DAC Pro feeding 2 Modulus-86 amplifiers which power full range Fostex FE126En drivers in the Fostex suggested hybrid horn/bass reflex cabinets, also Pioneer SE-305s driven straight from the Pi2Design DAC). I'm sticking with it though, purely for SD card wear reasons, as I do find SD card problems to be the most frequent causes of the issues I've had with Raspberry Pis over the years.
RE: Moving caches to SDRAM - aknaggbaugh - 04-23-2021
Update: this seems to be a bad idea on a 1GB Raspberry Pi, having /var/cache in RAM was causing my system to become unresponsive and there were kernel messages relating to memory allocation errors. I reverted and these problems have gone away. YMMV and maybe it works better on the Pi 4s with more RAM, or without the local display enabled, but I definitely wouldn't recommend it on the older Pis.