LSI HW RAID w/possible onboard cache issue - Can Cachecade save me ?

Allan74

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May 15, 2019
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I have a current media server that I am trying desperately to get a bit more life out of before I retire it for newer technology and have found that there may be a problem with the LSI RAID controller's onboard cache (soldered to board, non-removeable/non-upgradeable) as it has a habit of going offline during heavy writes when in write-back for no good reason, forcing a reboot (Windows).

The card runs flawlessly dumbed-down using write-through, albeit, slow without the write cache.

Can enabling cachecade and adding a SAS SSD (as the array is all SAS) as write cache buy me a bit more time with this setup, removing the controller's cache from the equation entirely ?

I don't want to take a chance and simply replace the controller with the same model, as I don't know what I will be getting and the price of a 100GB Enterprise SAS SSD is extremely cheap (if the plan were to succeed).

LSI 9261-8i (running HW RAID5)
SAS Dell/Seagate Constellations (all identical)
64bit Windows 7

thanks in advance,
Allan

ps. the controller did the same thing using SATA drives also.
 

Allan74

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May 15, 2019
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I can honestly say that these cards (as I have 2) run like egg cookers even at idle so I never gave THAT much thought to the problem being heat related, but I have been cooling each card with it's own 120mm fan blowing over top and still seem to experience problems from time to time.
 

Allan74

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May 15, 2019
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Back to the original topic..... Will Cachecade save me, or, provide the server in question with a bit more life if there is in fact an onboard RAID Cache problem ?
 

Dreece

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Jan 22, 2019
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Cachecade works with the dram cache, if the cache goes out, I believe cachecade will go with it, it isn't a 'this or that' philosophy, SSD caching 'cachecade' is an extention to the caching technology of the card and kicks in for writes when dram isn't big enough to serve the request (data going from dram to cache back to dram and so forth). That is how I understand it to function. Unfortunately I don't have a play system with cachcade where I can pull the dram cache to prove my presumption.

Just buy another card, as long as you buy cheap and sell cheap, you lose nothing, but at least you gain confirmation.
 

i386

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Mar 18, 2016
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Adaptecs maxcache doesn't use the controller ram for caching, I think Broadcoms cachecade has a similar implementation...
 

Dreece

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Jan 22, 2019
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Adaptecs maxcache doesn't use the controller ram for caching, I think Broadcoms cachecade has a similar implementation...
If you take the controller ram away, caching can't work, needs the ram to function, data doesn't go from ssd/onboard-flash down the pcie lanes without it buffering via the controller ram, I'd say it plays a significant role for caching irrespective of the underlying persistent cache storage medium. Take the ram away, maxcache/cachecade won't function right if at all. Though card will probably fail to initialise if onboard ram vanished anyway.
 

Dreece

Active Member
Jan 22, 2019
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@Allan74 - try using a free LSI key via megaraid software to enable CacheCade for 30 days, Google the license key. Keep in mind that after 30 days the cache ssd pool and all the arrays it is caching for will go offline and you will need to enter the same key again to re-enable a 30 day trial again.

If things work as you need, then you could just leave the trial key in there and as long as you don't reboot the machine, everything should continue to work even past 30 days, but the moment you reboot is when the controller checks if it has passed the demo timelimit or not.

You can always just buy the physical key, quite cheap these days. I have a spare cachecade physical key here in my parts bin somewhere, though need to check if it is a 2 pin or 3 pin type.
 

Allan74

Member
May 15, 2019
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Thanks guys.
It has become apparent in the last week or so that the problems may very well be deeper than just the controller.

I have been running a media server for home use off a SuperMicro C7X58 (chopped down X8SAX) and a Xeon L5638 for more years than I should at this point and have been running both of my LSi 9261-8i cards in it, as I never bothered to get my IBM SAS Expander working (BIOS upgrade required). Unfortunately, I went BIG into LGA1366 and still have multiple 6core Xeons and single and dual CPU boards, then lost interest when I bought my Skyline GT-R.....and now that I am back to computers after an injury, I simply have hobbled everything together to keep it working, as everyone knows, Netflix per month is far cheaper and less stressful when compared to hosting a home 20+TB media box.

It seems as of late, my Intel (onboard) Gigabit LAN speeds have dropped on both controllers down to 70-75MB/s (also tested add-in card with similar results), regardless of where I write to (array, SSD single etc) so I think this may very well be my board's PCH telling me that it has had enough, as it seems to be producing more heat than it ever has.

I may try and transfer all the hardware over to a Dual LGA1366 Xeon x5670 SuperMicro system that I have to buy me as much time as I can, as I don't want to really invest more into hardware, other than drives if needed.

As I have been running Win7x64 for the system's life, due to old versions of Plex Server compatibility with Windows Server, I think an OS upgrade, to Win10Pro may be in it's future as well, as Broadcom seem to have Win10 drivers for my cards.

thanks to all and I will report back if any other issues. Thank you.
 

Dreece

Active Member
Jan 22, 2019
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A GT-R? very very nice! Ferrari performance daily driver, just a pity the backseats are far from practical.
Now if you can spend as much as you spent on the ride on the homelab, you'd be grinning from ear to ear too. lol.
 

Allan74

Member
May 15, 2019
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It was an '89 R32 GT-R ...... I am a bit of a purist and don't accept the new 'GT-R' as part of Godzilla's family ;)
 
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