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A number of things which may account for this performance gap: Comparing 24 spindle RAID-10 vs 20 spindle RAID-0 volume write performance would be expected to max at 12x and 20x of a single disk respectively. So a ~2X slowdown off the bat isn't insane. You've made your chunk size is only 2KB. The default is 512KB. (supporting benchmarks). The actual ...


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If your OS is running directly on the hardware and you believe you have a hardware-based RAID the first step would be to use a tool like lshw to discover the type of Storage/RAID controller. After you have learned that you would probably need to do some Googling to find the software tools required to manage that RAID controller from your OS. If this was a ...


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OS disk-usage on SQL Servers are if anything minimal during normal operation. They only generate load during updates. What's more concerning is that you're placing your log and datafiles on the same spindles. This is quite the contrast to the recommended setup where you always try to separate the log I/O from the database I/O.. this also applies to tempDB ...


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Maybe http://www.netapp.com/us/media/tr-3298.pdf which has more details and references can help you understand the design?


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Hmm, I agree, it's vague. I've always worked with spares, so drives are added automatically. Perhaps you can hack that too: tw_cli /c0 add raidtype=spare disk=6 Then perhaps it will pick it up automatically.


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Besides increasing the number of physical disks, you need to modify Oracle to run more parallel processes. I do this with: NAME CURRENT_MEMORY_VALUE ------------------------------ --------------------- parallel_max_servers 32 parallel_min_servers 8 parallel_servers_target 32 parallel_threads_per_cpu ...


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The problem is that, in spite of your intuition, Linux software RAID 1 does not use both drives for a single read operation. To get a speed benefit, you need to have two separate read operations running in parallel. Reading a single large file will never be faster with RAID 1. To get the same level of redundancy, with the expected speed benefit, you need ...


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Redhat does not recommend RAID 1 w/ SSD and mdadm: During the initialization stage of these RAID levels, some RAID management utilities (such as mdadm) write to all of the blocks on the storage device to ensure that checksums operate properly. This will cause the performance of the SSD to degrade quickly. Chapter 21. Solid-State Disk Deployment ...


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I've seen that setup on database servers, where admins wanted to do full backups, but didn't want to have extended downtimes on the databases. They created raid setups with 3 mirrors, and when it was time to backup, quiesced the database, removed one disk from the raid, did the backup from that disk, and after backup was finished, put the disk back into the ...


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As long as you can load the correct drivers for the RAID controller from the OS you use to boot your server, you will be able to access the data on your RAID-5 array.


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This is a typical configuration for important data that needs to be accessed quickly, and database loads in general. If you have a RAID1 with two disks, and one of them fails, you are left with no redundancy until the rebuild is complete, so any defective sector on the remaining disk will cause an error (which is also why RAID5 systems die so often). Also, ...


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The Linux software RAID 1 implementation is a non-standard RAID level that can be composed of an odd number of disks, also called RAID 1E. Every strip is mirrored, normally over two of the disks, which allows you to recover from the failure of one disk. As with all RAID 1 it doubles the potential read performance compared to that of a single disk. With 3 ...


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This is a RAID using 3 disks, giving you additional read-speed and more fault-tolerance.


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I have successfully reconfigured a RAID 5 to RAID 6 with the PERC 6/i. All data was preserved. If my memory serves, I added 2 drives, with 1 used to extend the size of the RAID 5 array, and the other used to upgrade the RAID level from 5 to 6.


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Get into the Controller's BIOS, select the degraded array and press CTRL+R to rebuild the array.


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More harddrives generally do increase the theoretical IO performance. By what useful amount differs greatly on the method. In many real world applications (and for smaller numbers of disks) the increase in IO performance is not even close to linear. Scenarios where more disks don't increase the performance are for example those where the limits of the ...


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Increasing I/O throughput will almost always increase performance. However, there is no magic formula for how many hard drives should be used for a certain number of tables or databases. There are too many factors to consider: data size, schema design, write or read heavy, number of queries, etc. Aside from adding additional hardware it always helps to ...


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Problem fixed. Here's what i did: Ran a backup on Thursday night of C drive. I waited until Friday and ran check disc on the good partitions. all came back ok. Shut down the server. Unplugged the RAID 1 with the HD with bad sectors. I then inserted 2 new HD's with and created a fresh RAID 1. I then plugged the bad sector drive into a spare SATA port ...


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I'd be suspecting that BOTH drives had been replaced by the datacenter personnel and not just the one drive. Otherwise, you'd see one configured drive. A couple of things, a RAID1 situation does not necessary guarantee you from failure. I have had one drive fail in writing properly just to take the other drive with it strangely enough. Another thought, ...


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"Ready for Rebuild" is one of the worst errors you can receive on an HP ProLiant system. This indicates that the drive can't finish its rebuild because the disk you replaced is having trouble reading from its partner drive(s). Essentially this means that you have a failed disk and a failing disk. See the following: HP Proliant ML350 G5 SAS HDD Force LUN ...


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The spec indicates the max size possible using Dell proprietary disks offered for that server at the time, so it is largely irrelevant. The actual limit is 2TB per disk for the Perc5 (and many other controllers) but there is nothing stopping you from using a newer raid controller that supports bigger disks. An H700 for example is not supported but will work ...


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To configure RAID for HP ProLiant Servers download the newest SPP (Support Pack for ProLiant). It is an iso File. Boot from this iso (burn on dvd, put on usb drive, or connect via ILO) and there you can configure the RAID. You shouldn't configure a RAID without knowing the differences between the RAIDs. Have a look at this: ...


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Regarding the question about RAID I would advise you to read about the different types of it in Wikipedia, go through the pros and cons and decide which one you want and which ones the system allows you to implement (for example I have seen servers that only allows you to implement RAID 0 and RAID 5 through the BIOS). Keep in mind that there is no "commonly ...


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Ubuntu is not a good match for the HP ProLiant ML350e server hardware. Ubuntu is not supported for use with the hardware RAID controller on that system. Please see the following question for more detail: Installing Ubuntu 12.04 on HP Proliant DL380e with 1TB SAS Drive Ubuntu is certified for the ProLiant ML350e only if the Dynamic Smart Array controller is ...


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With md software RAID, which you've indicated you have, you can usually just unmount the RAID device, and mount the healthy member, eg with /dev/md1, made up of /dev/sda5 and /dev/sdb5, the latter being faulty, and the whole thing mounted on /data, you could do: umount /data mount /dev/sda5 /data However, with the tiny amount of information you've given ...


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I've run into the exact same SNAFU on a CentOS 6 machine. My kernel has 64-bit support, but the file system wasn't originally formatted with the 64-bit flag set. No >16TB support. :-( I can confirm that tune2fs will be no help here. You cannot convert an ext2/3/4 file system to 64-bit. I'm lucky though in that I'm using LVM on top of my MD array, so I've ...


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Firstly yes you can do this on a P420i, presumably this is in a DL380 G7/Gen8? anyway you can do this via 'RAID Level Migration' on that card, you don't mention which OS you want to do this on but it's possible either 'in-OS' via the ACU utility on Windows or the Linux CLI command (whose name changed a while back and isn't HPACUCLI but I've forgotten ...


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I'll rarely use nested RAID levels like RAID50 and RAID60 these days. And if I do, it's usually part of a software RAID solution like ZFS. A lot of this is due to having better methods to avoid high spindle counts and the availability of larger disks. Controller capabilities: This is the biggest factor, as many controllers don't support RAID50 or RAID60. ...


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In short, yes... you would have a problem with RAID6 and using a smaller drive. RAID6 itself has no way to dynamically re-size the RAID to a smaller disk. You must either: have a RAID controller capable of dynamically resizing the RAID volume copy your data elsewhere, and completely rebuild the RAID and then restore the data back to the volume. I have ...


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Backups are hard. And absolutely required. As marc99 pointed out, disconnecting drives physically from the enclosure is not a safe option. First, you need to decide what data is actually important. You mention MySQL and it's taking around 6gb. Is anything ELSE on the server valuable? Have you looked into compression? Does that save you anything? ...


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You should make a decision on the storage strategy based on needed capacity/performance. Backup solution should be based on time to retrieve your backup/time window for the backup to run. About storage and performance, you should consider: disk type (SATA/SAS vs SSD): capacity vs performance number of disks: more disks, more performance raid type About ...


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The problem here is the write back feature of LSI controller, which only make sense for HDD´s. For SSD´s always use write through and no read ahead and DirectIO (even with RAID5). Then you see the expected performance with more SSD´s...



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