minimum frequency at which blocks are allowed to be cached into level-2 storage Topic is solved

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tester000001
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minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by tester000001 »

hello. this is from changelog
Version 0.9.9 beta (2014-01-28)
Tune the level-2 cache algorithm. Changing the default value of minimum frequency at which blocks are allowed to be cached into level-2 storage. In version 0.9.8 this value is 3, now is 1.
Support to set the minimum frequency at which blocks are allowed to be cached into level-2 storage (CLI only, option -f).
i haven't found this feature has been remover in later versions. but

Code: Select all

 rxpcc ? new
doesn't have this option
for example I watched movie from hdd. with this parameter is "1" movie will be cached to L2. for what.
For example 5 or 10 time is good for long term use and in L2 will be only most frequently used data.

Q: Is "option -f" still available in 3.0.9, if yes -- how to use
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by Support »

No, this option has been removed since v2.0 because new design was introduced in v2.0.
tester000001
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by tester000001 »

there must be posted in changelog. I tried to enable it whole day thinking it's still in.
will it back. at GUI for convenience?

P.S. and how about caching blocks depending of size of operation.
for exampe HDD speed is around 100 MBps, HDD IOps is around 100. that means no need to cache read operations greater than 1 MB. or 2 MB depending of certain disk
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by neatchee »

for exampe HDD speed is around 100 MBps, HDD IOps is around 100. that means no need to cache read operations greater than 1 MB. or 2 MB depending of certain disk
This doesn't really make sense to me. Even if the file is only 1MB it will be faster to read off of an SSD or NVMe.
tester000001
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by tester000001 »

neatchee wrote: Tue May 21, 2019 1:30 am
for exampe HDD speed is around 100 MBps, HDD IOps is around 100. that means no need to cache read operations greater than 1 MB. or 2 MB depending of certain disk
This doesn't really make sense to me. Even if the file is only 1MB it will be faster to read off of an SSD or NVMe.
optimisation? tuning (even cli only)? nah
no doubt. it's better to be healthy and rich than ill and poor. wish you 8 tb optane for 250$
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by Support »

tester000001 wrote: Mon May 20, 2019 9:27 pm for exampe HDD speed is around 100 MBps, HDD IOps is around 100. that means no need to cache read operations greater than 1 MB. or 2 MB depending of certain disk
Usually most read operations at the block level are less than 1MB. And the cache performance is our first consideration. Additional size processing may affect the performance. I'm sorry that In the near feature we don't plan to do this.
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by tester000001 »

I'm sorry that In the near feature we don't plan to do this.
thanks for answer. understood. agreed. but will you back counter "minimum frequency at which blocks are allowed to be cached into level-2 storage"?
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

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tester000001 wrote: Thu May 30, 2019 2:56 pm but will you back counter "minimum frequency at which blocks are allowed to be cached into level-2 storage"?
Yes, we're thinking about this.
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Re: minimum frequency at which blocks are allowed to be cached into level-2 storage

Post by tester000001 »

Yes, we're thinking about this.
OMG. thats great!
i understood that too high values results long period of collecting statistics. the bigger == the longer. but this is the idea! olny most frequently nearly static data.
values will be between 1 and 255?) hopes for at least 10 please!)
thanks for feedback!
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