Level 2 cache not increasing speed

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InquiringMind
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Re: Level 2 cache not increasing speed

Post by InquiringMind »

rajdude wrote: Thu Aug 19, 2021 1:32 amAny thoughts?
Just that you seem to have spent quite some time confirming the points made above - that the SATA connection of your SSD is not an issue, that your CPU is the bottleneck and that L1 cache is not worth enabling unless you can dedicate significant memory to it.

I do wonder why you are still relying on LAN benchmarks when there are plenty of good hard disk ones like CrystalDiskMark (free, simple quick test) or HDTune (trialware, more thorough testing). Using these means avoiding network bottlenecks - which, if they exist on your system, can be dealt with separately.

Frankly, using an Atom in a server to lower power consumption is insane - you are only saving a few tens of watts compared to a low-end Xeon and giving up an awful lot of computing power - Atoms should only be considered where power usage is critical, like in a battery operated system. If you want to save power on a 24/7 system, make sure the monitor powers down after a period of inactivity (that's 70-150W for a flat screen, depending on size and backlight type) and that you are running the lowest-spec graphics card you can get away with (high-end ones are real power-hogs). Assuming that your system sees constant or near-constant use, ensure that the HDDs are set to *not* power down (starting them up will take 10-20W each) and consider replacing them with SSDs.

Is PrimoCache for you? I'd suggest balancing your system first.
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Re: Level 2 cache not increasing speed

Post by Support »

Change the block size to 32KB or 64KB, it might help.
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Re: Level 2 cache not increasing speed

Post by Support »

You may also test the native speed of SSD and RAID HDD. If SSD is slow, then L2 speed also will become slow.
rajdude
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Re: Level 2 cache not increasing speed

Post by rajdude »

Thank you for your input and bear with me while I attempt to answer your posts:


InquiringMind wrote: Thu Aug 19, 2021 8:28 am Just that you seem to have spent quite some time confirming the points made above - that the SATA connection of your SSD is not an issue, that your CPU is the bottleneck and that L1 cache is not worth enabling unless you can dedicate significant memory to it.
Agreed! :-)
InquiringMind wrote: Thu Aug 19, 2021 8:28 am
I do wonder why you are still relying on LAN benchmarks when there are plenty of good hard disk ones like CrystalDiskMark (free, simple quick test) or HDTune (trialware, more thorough testing). Using these means avoiding network bottlenecks - which, if they exist on your system, can be dealt with separately.
Well, first: I am NOT running the test over the network, you are mistaken. I have mentioned this earlier......that I am running this test on the server itself.

Second, my ultimate goal is high network throughput. The other tools (and I am well aware of them) don't do over the network testing (also). Using the same tool on my workstation and on the server itself, gives me an apples-apples type of test.
InquiringMind wrote: Thu Aug 19, 2021 8:28 am Frankly, using an Atom in a server to lower power consumption is insane - you are only saving a few tens of watts compared to a low-end Xeon and giving up an awful lot of computing power - Atoms should only be considered where power usage is critical, like in a battery operated system. If you want to save power on a 24/7 system, make sure the monitor powers down after a period of inactivity (that's 70-150W for a flat screen, depending on size and backlight type) and that you are running the lowest-spec graphics card you can get away with (high-end ones are real power-hogs). Assuming that your system sees constant or near-constant use, ensure that the HDDs are set to *not* power down (starting them up will take 10-20W each) and consider replacing them with SSDs.

Is PrimoCache for you? I'd suggest balancing your system first.
Well, the reason for using Atom is simply low power consumption. I am wary of high electricity bills. I did not chose to put an Atom on it, SuperMicro makes plenty of Atom motherboards (Atom is soldered onto the mobo)...There is a real reason why a well known dedicated server company makes Atom based boards. There is a market for it....I am one of those people :mrgreen:

This server costs me around 6 dollars a month / 74 dollars a year. I built it well over a decade back....so that has cost me $740
Just for contrast, the workstation I built around the same time ago, used around 300 watts. That would have cost me $315 per year / 3150 dollars!
So i chose to take the seemingly insane route to get the Atom instead :D

(yes, a current generation machine will suck up much less power...but I will have to spend around 500-800 bucks to get a new mobo+CPU+ram etc. Maybe it is worth it, maybe not....a ROI analysis needs to be done :-)

This low power machine has served well, because all I ask of it is to serve my photos and videos on the home network.....which is very light use. The machine runs headless, no monitor attached. It has IPMI for remote management. Also RDP is there, once Windows OS has booted up.

I have a 14TB HDD array in it, using 5 NAS HDDs
Using SSDs for that size of array would be very expensive...but yes, they will consume lower power :thumbup:

So there you have it........yes you are correct, my config for the server is crappy.
But there is a valid reason for it to be so crappy..........and it works for me. :ugeek:

However, if I want more ooomph from it.......more network throughput....I need to upgrade its hardware.
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Re: Level 2 cache not increasing speed

Post by Jaga »

You're testing two layers at the same time - local drive access and network speed. Never do this, since it mucks up results and never tells you what's going on.

On the machine you have Primocache installed: use CrystalDiskMark to test drive speed when Primocache is disabled, then when it is enabled. Always use a test data size smaller than the cache size. If you have separate read/write space enabled, it's also going to screw with test results, so I recommend disabling separate space for read/write for testing purposes. That at least will let you know how much Primocache is affecting local (non-network) drive speeds. Then you can start testing the network layer separately to see what it is capable of. The network itself may be the bottleneck in this case.
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Re: Level 2 cache not increasing speed

Post by InquiringMind »

rajdude wrote: Thu Aug 19, 2021 7:56 pm Well, the reason for using Atom is simply low power consumption...This server costs me around 6 dollars a month / 74 dollars a year. I built it well over a decade back....so that has cost me $740...a current generation machine will suck up much less power...but I will have to spend around 500-800 bucks to get a new mobo+CPU+ram etc. Maybe it is worth it, maybe not....a ROI analysis needs to be done :-)
In that case, you might want to take a look at a Raspberry Pi (or something similar) - a very cheap and compact system with minimal power consumption (ARM have always outdone Intel in that regard). This will mean using Linux instead of Win10, but you'll save yourself all those activation hassles. ;)
rajdude wrote: Thu Aug 19, 2021 7:56 pm This low power machine has served well, because all I ask of it is to serve my photos and videos on the home network...
In that case, PrimoCache (and caching generally) may not offer much benefit. Firstly because media content doesn't benefit from read speeds in excess of what is needed for playback - and the most extreme case would be about 100MB/s for H.264 Level 6.2 (4K/8K UHD) compressed video which your RAID setup should manage easily (editing uncompressed video is quite another matter though).

That's assuming your server is serving files directly via SMB/CIFS - if it is supplying them via HTTP and generating a user-friendly webpage preview, then that again becomes a CPU issue.

The second reason is caching only benefits content that is accessed repeatedly - in the case of a media server it is more likely that each item of media is read once only, with the requester moving on to another item when done.

As such, I'd suggest keeping your SSD for your Windows installation and program files. If you get a second SSD, then it may be worth trying that for L2 caching.
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