Really bad performance when going from Write-Back to Write-Through in a LSI controller

Ever wonder what is the impact of write-through of an LSI controller in a real-world streaming server? Have no wonder anymore!

you can get several (multiple?) times slower with the write-through mode than if your controller were using the write-back mode of the cache

And it could happen any moment because when charging the battery of the LSI controller and you have set “No Write Cache if Bad BBU” the write-through would kick in. Of course, you can make a schedule for the battery charging/discharging process, but in general, it will happen and it will hurt your IO performance a lot!

In simple words a write operation is successful only if the controller confirms the write operation on all disks, no matter the data has already been in the cache.

This mode puts pressure on the disks and Write-Through is a known destroyer of hard disks! You can read a lot of administrator’s feedback on the Internet about crashed disks using write-through mode (and sometimes several simultaneously on one machine losing all your data even it would have redundancy with some of the RAID setups like RAID1, RAID5, RAID6, RAID10 and so).

srv ~ # sudo megacli -ldinfo -lall -aall
Adapter 0 -- Virtual Drive Information:
Virtual Drive: 0 (Target Id: 0)
Name                :system
RAID Level          : Primary-1, Secondary-0, RAID Level Qualifier-0
Size                : 13.781 TB
Sector Size         : 512
Mirror Data         : 13.781 TB
State               : Optimal
Strip Size          : 128 KB
Number Of Drives per span:2
Span Depth          : 6
Default Cache Policy: WriteBack, ReadAdaptive, Direct, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAdaptive, Direct, No Write Cache if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy   : Disk's Default
Encryption Type     : None
Bad Blocks Exist: No
Is VD Cached: Yes
Cache Cade Type : Read Only

Exit Code: 0x00

As you can see our default cache policy is WriteBack and “No Write Cache if Bad BBU”, the BBU is not bad, but charging!
Keep on reading!

Dell Inspiron 7352 with 16G DDR3L single SODIMM RAM – it works!

What a great piece of hardware is Dell Inspiron 7352! In the year 2015, this laptop was on the market with 8G DDR3L SODIMM and this was the maximum single SODIMM RAM available at the moment! Still, DELL had decided to make this laptop with memory slot not soldered on the motherboard! After around two years Crucial made available a single 16G DDR3L SODIMM – Crucial CT25664BF160B DDR3L 1600 MT/s PC3L-12800 SODIMM 204 Pin Memory 16gb and DELL made a BIOS update, which made the laptop to support 16G RAM!
This article is to confirm that

DELL Inspiron 13 7352 laptop (i7-5500U 2.40GHz) works perfectly with Crucial 16G DDR3L!

The BIOS is A08 (11/13/2015), probably it would work with all later version after A08, too! At present, there are newer BIOS versions, but we haven’t flashed our BIOS yet!
Keep on reading!

Update supermicro X10SLH-F firmware BIOS under Linux with the SUM cli

As you can see our product is:

product: X10SLH-F/X10SLM+-F

The same string is in our KVM IPMI: “Product Name: X10SLH-F/X10SLM+-F” and in the BIOS, but if you go the supermicro site you will find that

  • X10SLH-F has C226 chipset (supports video in the CPU)
  • X10SLM+-F has C224 chipset

and because we use the video in the CPU we know our motherboard is X10SLH-F and we downloaded the BIOS firmware for it. You also could check your chipset with lshw command.

STEP 1) Download and unpack the SUM (Supermicro Update Manager) and the BIOS zip file

Unpack the SUM (Supermicro Update Manager), here you can find a detail information about SUM – Update supermicro server’s firmware BIOS under linux with the SUM cli

[root@srv1 ~]# tar xzvf sum_2.0.0_Linux_x86_64_20171108.tar.gz 
[root@srv1 ~]# unzip
   creating: x10slh8.510/
  inflating: x10slh8.510/AFUDOSU.SMC  
  inflating: x10slh8.510/ami.bat     
  inflating: x10slh8.510/Readme for AMI BIOS.txt  
  inflating: x10slh8.510/x10slh8.510  
[root@srv1 ~]# cd sum_2.0.0_Linux_x86_64
sum_2.0.0_Linux_x86_64/                 sum_2.0.0_Linux_x86_64_20171108.tar.gz  
[root@conv1 ~]# cd sum_2.0.0_Linux_x86_64

STEP 2) Flash the BIOS file with sum cli.

Here you can see what to expect flashing the BIOS firmware.

[root@srv1 sum_2.0.0_Linux_x86_64]# ./sum -c UpdateBios --file ../x10slh8.510/x10slh8.510 
Supermicro Update Manager (for UEFI BIOS) 2.0.0 (2017/11/08) (x86_64)
Copyright©2017 Super Micro Computer, Inc. All rights reserved
Reading BIOS flash ..................... (100%)
Checking BIOS ID ...
Writing BIOS flash ..................... (100%)
Verifying BIOS flash ................... (100%)
Checking ME Firmware ...
Putting ME data to BIOS ................ (100%)
Writing ME region in BIOS flash ...
 - Update success for /FDT!!
 - Updated Recovery Loader to OPRx
 - Updated FPT, MFSB, FTPR and MFS
 - ME Entire Image done
WARNING:Must power cycle or restart the system for the changes to take effect!
[root@srv1 sum_2.0.0_Linux_x86_64]# reboot

During the BIOS flashing your console could have seemed unresponsive for several minutes, but it is OK, the flash process is about 10 minutes. Then reboot and wait for several automatic resets of your system and after that when your system reaches the OS boot you should reboot again and reset your BIOS to the optimized defaults and then you can tune it as it was before.

In some rear cases you could receive “Critical Error” – “FDT is different.” you should reboot and repeat the procedure, more information here – Update supermicro server’s firmware BIOS under linux with the SUM cli


Some commands to find the exact information for the server motherboard.

[root@srv1 ~]# lshw|grep -A 14 "core$"
       description: Motherboard
       product: X10SLH-F/X10SLM+-F
       vendor: Supermicro
       physical id: 0
       version: 1.01
       serial: ZM1111111111
       slot: To be filled by O.E.M.
          description: BIOS
          vendor: American Megatrends Inc.
          physical id: 0
          version: 3.0a
          date: 12/17/2015
          size: 64KiB
[root@srv1 ~]# lspci |grep -i c226
00:1f.0 ISA bridge: Intel Corporation C226 Series Chipset Family Server Advanced SKU LPC Controller (rev 05)
conv2 ~ # lspci -vvv|grep -i c226
00:1f.0 ISA bridge: Intel Corporation C226 Series Chipset Family Server Advanced SKU LPC Controller (rev 05)
        Subsystem: Super Micro Computer Inc C226 Series Chipset Family Server Advanced SKU LPC Controller

Supermicro server cannot enter BIOS with F2, DEL or other when UEFI mode OS is installed

If you happen to have a supermicro server (X10SLH-F) and install Linux in UEFI mode in our case CentOS 7 and you want to enter the BIOS you’ll be surprised that you cannot with the keys provided in the very same BIOS boot screen – F2, DEL. The F11 and F12 also does not work for menu selection and network boot!

Even if you manage to press the DEL key and you see on the screen “Entering BIOS setup…” – the server WON’T enter BIOS, but will continue with the UEFI BIOS boot drive!

So what to do? Ammm break temporary your system by removing (renaming or moving) the EFI directory in your efi boot partition, resetting your server and holding pressed DEL key (again) on all start up screens of the server. When the UEFI BIOS boot entry is not valid any more and there are no other boot devices (and probably because we pressed DEL key) we were able to enter in the BIOS without remote hands on the collocation side or any other intervention on the server.

[root@srv ~]# mv /boot/efi/EFI/ /boot/efi/EFI_org
[root@srv ~]# reboot

This is the path in CentOS 7 and our standard partition layout:

[root@srv ~]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda3         26G  4.5G    20G  19% /
devtmpfs         7.8G     0   7.8G   0% /dev
tmpfs            7.8G     0   7.8G   0% /dev/shm
tmpfs            7.8G  8.5M   7.8G   1% /run
tmpfs            7.8G     0   7.8G   0% /sys/fs/cgroup
/dev/sda2        976M   98M   812M  11% /boot
/dev/sda1        200M  9.8M   191M   5% /boot/efi
tmpfs            1.6G     0   1.6G   0% /run/user/0

DO NOT forget to remove all other (virtual) CD/DVD ROM Devices and temporary disable your network PXE Server (if you have any in the network)

Because it when the UEFI BIOS cannot find the EFI file saved in the UEFI BIOS BOOT drive it might follow the boot order before entering the BIOS!

Enter the bios by remote console on our X9 boards with UEFI bios

Apparently there is an issue with X8 and X9 supermicro boards in UEFI mode BIOS:
So for someone it could be useful pressing and holding “ESC” + “-” or F4 to enter the UEFI BIOS, but we could not make it because of the IPMI KVM we used to manage the server.

Install the new storcli to manage (LSI/AVAGO/Broadcom) MegaRAID controller under CentOS 7

After the acquisition of LSI there was a major change with the management console utility for the MegaRAID controllers. The utility was renamed from MegaCli (MegaCli64, megacli) to

storcli (storcli64)

We have new controllers like AVAGO MegaRAID SAS-9361-4i and really old ones like LSI 2108 MegaRAID (in fact Supermicro AOC-USAS2LP-H8iR) and the two controllers could be manage with the new cli. even the old controller, which is on more than 8 years could be manage by the new cli.
Interesting fact is that the storcli output and argument syntax and is almost identical to the one really old cli – tw_cli – the 3Ware management utility. As you know LSI bought 3ware RAID adapter business in 2009.
Keep on reading!

AVAGO MegaRAID SAS-9361-4i with CacheCade – create a new virtual drive RAID5 with SSD caching

Here is howto article for creating a RAID5 device in MegaRAID SAS-9361-4i with SSD caching. First and really important thing is to have the CacheCade ability to the controller, which should be purchased because it is a software add-on.
To have an SSD caching your virtual raid drive (probably hard disk drives) with a MegaRAID controller one setup is the following:

  1. LSI LSI00415 MegaRAID 9361-4i SGL
  2. LSI LSI00293

And it is advisable to have Cache Protection to protect your setup (it is extra protection to the battery kit – it is not the same) – LSI LSI00418 LSICVM02.

You can check also our AVAGO MegaRaid SAS 9361-4i with CacheCade and CacheVault BIOS configuration utilities review.

Here are the steps to create a RAID5 device with SSD caching using the BIOS Configuration Utility:

STEP 1) Supermicro device initialization

main menu
Start up your server

Keep on reading!

AVAGO MegaRaid SAS 9361-4i with CacheCade and CacheVault BIOS configuration utilities review

Here is the screenshots’ review of LSI LSI00415 MegaRAID 9361-4i SGL controller with CacheVault Accessory kit LSI LSI00293. The controller has 3 hard disk and an SSD for the cache vault.
As you can see we use LSI, but in deed this is the AVAGO controller. First it was LSI, which was acquired by AVAGO and then AVAGO acquired Broadcom and rebranded to Broadcom. It is good to know it how these names are connected, because any controllers still use them in BIOS, management console cli, manuals and so on. You are going to see that in the controller’s BIOS and controller initialization boot up you can read only AVAGO – no LSI or Broadcom. Probably the most famous and familiar name of the three company names is LSI (hardware controller).
The screenshots are from the BIOS of “LSI LSI00415 MegaRAID 9361-4i SGL” with LSI LSI00293, CacheCade and LSI LSI00418 LSICVM02 – CacheVault Accessory kit.

So as you see you need two additional features to have a SSD as a cache device in your LSI (AVAGO/Broadcom) controller!

Check out our article AVAGO MegaRAID SAS-9361-4i with CacheCade – create a new virtual drive RAID5 with SSD caching.

SCREENSHOT 1) Booting the controller and checking the devices.

main menu
LSI controller Booting

Keep on reading!

LSI MegaRAID 2108 freezes with abort command and all processes hang up in disk sleep

It happened to one of our old LSI MegaRAID 2108 controllers (AOC-USAS2LP-H8iR (smc2108) with 36 disk, 32x2T and 4x8T) to freeze and most of the processes hang up with Disk sleep. The server was up, the network was working, but no login could be successful. A hard reset was executed with the IPMI KVM. The server started up, the MegaRAID controller booted with a warning that it was shutdown unexpectedly so there could be possible loss of data and to accept it by pressing any key or “C” to boot in the WebBIOS of the controller.

To summarize it up: the LSI controller hangs up when is in the following modes:

  1. Background Initialization
  2. Check Consistency

Aborting and disabling the modes above let out controller to work till replacement. If you experience any kind of strange disk hangs or freezes you can try our solution here! Check below to see how to do it yourself.

Keep on reading!

Update firmware of AOC-USAS2LP-H8iR (smc2108) – LSI 2108 MegaRAID Hardware Controller

This card


is really old (probably 7-9 years), but still it works, so you can check if you are with the latest and greatest firmware. Hope the latest fixes more things than it beaks. To flash the firmware you need Megaraid cli and the firmware file, the two files you check in the sub-directories of They are still there despite this product is discontinued. In this URL these are the latest, tested and verified versions by Supermicro so it is advisable to download them from this link or at least use the same versions if they are not available (in the future, now they are still available).
As you know LSI (they bought 3ware RAID in 2009) was bought by Avago (2013), then Avago bought Broadcom (2016 and renamed itself to Broadcom, 2018), so not so easy to find stuff for such old hardware (which still works). So this old MegaRAID controller is better managed by MegaCli despite you can do it with “storcli”, which is a modification of the tw_cli utility of 3ware RAID.

Keep on reading!

Update BIOS motherboard ASUS Zenith Extreme x399

This time we show what to expect when updating your UEFI BIOS of your ASUS Zenith Extreme (chipset x399) – a pretty good and performance setup! Here we update the UEFI BIOS from the BIOS itself – in fact, no OS is needed! This motherboard has a built-on utility called

Asus EZ Flash 3 Utility

which is started from the BIOS and it could read your NTFS or FAT filesystem to locate the update firmware file or the easy way to get connected to the Internet, check, download and install the update if any!
So here some screenshots to how to perform the update from 1003 to 1402 – it is easy and safe just couple of reboots needed – total of 4 (but in your case may vary).

STEP 1) Press DEL or F2 to enter your UEFI BIOS

main menu

Keep on reading!