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6

perhaps, you clean up apache's logs recently? if so, try to restart apache after that as well and you should regain your space back. run fsck as your filesystem may be corrupted. few ways to clean up your logs: setup logrorate (better way). echo > $FILE (dirty way).


2

hdparm -T will essentially test the performance of reading disk caching, which is CPU and memory. This tests what read speeds you would get when files are cached in memory (see the cache section for the free command). The nearline SAS drives aren't full SAS drives. They have the same benefits as SAS drives as they use the SAS interface, but are still ...


3

6 Gbs is the speed of the SAS link, not the IO profile of a single disk. Typically the speed in a SAS backplane will be negotiated down to the lowest common denominator so you'll find slow disks that still support high-speed SAS links to allow you to mix disks in a single (external) enclosure or backplane, or to benefit from parallelised IO spread out ...


0

rsync anyone? make a few folders, one for each drive, move data that will occupy one drive, then just do a check with rsync, not actually move the data. check man page


0

To mark it as answered I repeat my comment above as an answer here: I found the issue and its solution, it is strange, but the following operation helped: before installing ESXi I booted from linux live cd and checked all my disks. If did full read/write test to the disk it did not have errors after during install. So I went and wiped all drives and ...


1

Even though tuning kernel parameters stopped the problem, it's actually possible your performance issues were the result of a bug on the Adaptec 5405Z controller that was fixed in a Feb 1, 2012 firmware update. The release notes say "Fixed an issue where the firmware could hang during high I/O stress." Perhaps spreading out the I/O as you did was enough to ...


0

The very, very bottom of the kernel documentation on blkio controller includes the note: What works Currently only sync IO queues are support. All the buffered writes are still system wide and not per group. Hence we will not see service differentiation between buffered writes between groups. Practically, this means that write operations ...


0

Well, you're not going to be able to "move partitions around" by converting the disk to dynamic, but you will be able to extend the partition you want by doing so. As to what is affected by the change to dynamic disks, these days, the answer is pretty much nothing. You won't be able to boot an OS older than Windows 2000 from a Dynamic disk, older versions ...


2

There are several options, depending on what resources you have available: If you have the OS install DVD, you can boot from that (insert the DVD, then either hold the "C" key at startup, or hold Option key and select the DVD in the startup manager). There's a "Utilities" menu in the installer that'll let you run Disk Utility, which can either create a ...


1

If you assume all else is equal, performance characteristics of disks of larger capacity don't change very much. An 10K RPM FC drive has very similar characteristics regardless of whether it's 300GB or 3TB. The platters rotate at the same rate, and the heads seek at the same speed. Sustained throughput likewise - not much difference. This is the root of a ...


0

If you are rotating disks (not SSD) then everything else being equal, transfer speed is higher if you use the outer tracks of the disk. That would happen automatically if you use a disk that is only partially filled. At the same time, if a disk is only partially filled, your average head movement would be less, and the number of head movements would be less ...


7

One place where there is a direct relationship between disk size and IOPS is in the Amazon AWS Cloud and other "cloudy services". Two types of AWS services (Elastic Block Store and Relational Database Service ) provide higher IOPS for larger disk sizes. Note that this is an artificial restriction placed by Amazon on their services. There is no ...


7

To answer your question directly - all other things being equal = no change whatsoever when GB changes. You don't measure IOPS with GB. You use the seek time and the latency. I could re-write it all here but these examples below do all that already and I would simply be repeating it: http://www.ryanfrantz.com/posts/calculating-disk-iops/ ...


11

I know this is probably a hypothetical question... But the IT world really doesn't work that way. There are realistic constraints to consider, plus other things that can influence IOPS... 50GB and 100GB disks don't really exist anymore. Think more: 72, 146, 300, 450, 600, 900, 1200GB in enterprise disks and 500, 1000, 2000, 3000, 4000, 6000GB in ...


3

The performance added to the storage scales with each spindle added. The rotational speed of the drive is the biggest factor, so adding a 10k RPM drive will give more performance (in terms of IO/s in random IO or MB/s in streaming IO) than a 7.2k RPM drive. The size of the drive has virtually no effect. People say small drives go faster simply because you ...


4

I should point out that IOPS are not a great measurement of speed on sequential writes, but lets just go with it. I suspect the seek and write times of disk heads is pretty consistent despite the size of the disks. 20 years ago we we're all using 60GB disks with (roughly - certainly not linearly) the same read/write speeds. I am making an educated guess ...


4

This is correct... kinda. Use lsscsi. The SCSI device nodes correspond to the controller/target/device naming you see in VMware. Extreme example: root@vdp1:~/#: lsscsi [0:0:0:0] disk VMware Virtual disk 1.0 /dev/sda [0:0:1:0] disk VMware Virtual disk 1.0 /dev/sdb [0:0:4:0] disk VMware Virtual disk 1.0 /dev/sdj ...


0

Microsoft suggest the following updates to fix this issue: KB2920193 KB2916395 KB2867201



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