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12
votes
7answers
6k views

How do storage IOPS change in response to disk capacity?

All other things being equal, how would a storage array's IOPS performance change if one used larger disks. For example, take an array with 10 X 100GB disks. Measure IOPS for sequential 256kb block ...
10
votes
5answers
4k views

ZFS: Redistribute zvol over all disks in the zpool?

Is there a way in which ZFS can be prompted to redistribute a given filesystem over the all of the disks in its zpool? I'm thinking of a scenario where I have a fixed size ZFS volume that's exported ...
9
votes
2answers
7k views

Measuring IOPS in Linux

How would I find out how many IOPS my Linux system can handle?
7
votes
2answers
9k views

Relation between disk IOPS and sar tps

I'm trying to estimate IOPS requirements of my application running on 32-bit CentOS 6.2. I started to take some measurement on a machine with SATA disks and I'm quite confused of difference between ...
6
votes
2answers
6k views

Can I determine IOPS on a disk array using bonnie++?

I would like to measure the read and write performance of a RAID6 array verses a RAID10 array. I understand that bonnie++ can be used to calculate disk performance, but the numbers produced by bonnie++...
5
votes
7answers
2k views

setup lowcost image storage server with 24x SSD array to get high IOPS?

I want to build let's name it a lowcost Ra*san which would host for our social site the images (many millions) we have 5 sizes of every photo with 3 KB, 7 KB, 15 KB, 25 KB and 80 KB per Image. My ...
5
votes
2answers
3k views

Find current IOPS usage of EBS volume from my application on AWS EC2

I am relatively new to AWS and disk performance. I am trying to figure out how much provisioned IOPS does my application need to perform well. Currently My PHP and MySQL application is hosted on EC2 ...
5
votes
1answer
3k views

Will a SSD storage perform like a magnetic for small root volumes in AWS EC2?

I have a t1.micro instance with 8GB of magnetic EBS volume as it's root disk with a LAMP environment on it. I thought that I will upgrade it to t2.micro with 8GB of General Purpose SSD volume. ...
5
votes
1answer
9k views

Amazon: How do I know if I need Provisioned IOPS?

We recently moved to Amazon Web Servers and are still learning our way around. Our EC2 Web instance and our RDS MySQL instance (right now we only have 1 of each) seem to be chugging along okay. But I ...
4
votes
1answer
4k views

Why does storage's performance change at various queue depths?

I'm in the market for a storage upgrade for our servers. I'm looking at benchmarks of various PCIe SSD devices and in comparisons I see that IOPS change at various queue depths. How can that be and ...
4
votes
1answer
2k views

Estimate IOPS for an Amazon EBS volume using Windows PerfMon

I'm evaluating moving our aging infrastructure to Amazon's AWS and am trying to estimate costs. I know our current disk space requirements, bandwidth, and most of the other variables that will affect ...
4
votes
1answer
7k views

High iowait for unknown reason

I'm having a hard time figure out the reason cause high iowait on my server. This is log of iostat -xm 5 5 Linux 2.6.32-358.6.1.el6.x86_64 (prod-1.localdomain) 09/28/2013 _x86_64_ (16 CPU) ...
4
votes
1answer
1k views

What is the size of an IO Operation (IOP) in AWS EBS?

My research suggests that both the standard and the maximum (kernel limitations) block size for modern file systems (ext4, xfs) is 4KB. However, AWS allows IO operations as large as 256KB and says ...
4
votes
1answer
539 views

ESXi 5x: Changing number of IOPS per path sees dramatic improvements

I'm a bit embarrassed that I've never seen or used the -iops parameter as part of the esxcli deviceconfig options. I stumbled upon an article and proceeded to benchmark before and after using various ...
4
votes
1answer
1k views

How to calculate the required EBS PIOPS for our mongo server?

We want to use provisioned IOPS EBS volume on our mongo machines, I'm a bit confused on how to calculate the number of provisioned IOPS to use. Currently we're getting an average of 25 IOPS (read + ...
4
votes
1answer
499 views

Low SSD write IOPS (~100)

I am experiencing very low IOPS with a SSD in my server. I noticed this when running a mysql database server, which performed very bad when there were many (~100 per second) updates to an InnoDB ...
3
votes
2answers
3k views

8Gb Fiber Channcel HBA vs. 10 Gb SPF+ Converged HBA

I am putting a Dell server together, more specifically R720. I have to select the correct Host Bus Adapter. This HBA on R710 will connect to a storage device. I am confused between these two: QLogic ...
3
votes
2answers
2k views

IOmeter IOPS on Win2k3,Win2008, and Ubuntu 10.04

Summary: Given the same hardware, Ubuntu outperforms Win2k3 by about 50 percent when it comes to IOPS. Win2008R2 initially performs the same as Win2k3, but it gradually gains performance until it is ...
2
votes
3answers
7k views

Disk IOPS count in GNU/Linux

I can't find information about ways to count disk iops in GNU/Linux for some time period. I saw iostat, but I'm not sure it is right way. Also i need tool, that can count iops for all time since ...
2
votes
1answer
1k views

Estimate the IOPS in RAID 10

According to http://en.wikipedia.org/wiki/IOPS For example SAS disks provide ~200 IOPS each. For RAID 10 consisting of 4 such disks. How much IOPS I could expect for that array? I would think it ...
2
votes
1answer
3k views

gluster IOPS performance

Can "gluster" serve FLV files without any front-end server layers just using the built-in HTTP protocol ? How would the IOPS compare to standard apache serving? Would gluster help me with I/O limits ...
2
votes
2answers
851 views

How to determine IOPS needs after getting the Transfers/sec data?

Let's say that I have gathered Disk Transfers per second data for 2x24 hours period, i.e., instantaneous sampling of data every 15 seconds. What statistical analysis can/should I apply to the samples ...
2
votes
1answer
746 views

Is basing storage requirements based on IOPS sufficient?

The current system in question is running SBS 2003, and is going to be migrated on new hardware to SBS 2008. Currently I'm seeing on average 200-300 disk transfers per second total across all the ...
2
votes
1answer
604 views

really low iops on ssd raid (lower than 1000)

I'm having serious performances problems on a server, with really low iops. server : ProLiant DL360p Gen8 with HP Smart Array P420i Controller (firmware v6) with 4x Samsung 840 - 512GB on raid 1+0 ...
2
votes
1answer
1k views

Getting IOPS of the processes on Linux

So, what value should we read to get the in out operations per second per process? I've tried /proc/[pid]/io which returns these values: root@node:~# cat /proc/31597/io rchar: 213260190 wchar:...
2
votes
3answers
1k views

SAN spec'ing and IOPS counters

I'd like to make sure that I'm measuring IOPS correctly across Windows and Linux servers. We're busy trying to figure out which SAN would best suit our environment and measuring IOPS across our ...
2
votes
1answer
2k views

Does ZFS really stripe across every vdev, even in very large zpools?

I have read that ZFS stripes the data in a zpool across all top-level vdevs, assuming all vdevs are added at the beginning of the pool's life. Everything I have read seems to regard this as a good ...
2
votes
1answer
44 views

Different IOPs measured on server and storage

so I have this strange behavior that I can not explain to myself - hopyfully someone here can. We received some server (hardware) and mounted an NFS drive. We plan to use these servers as Splunk ...
2
votes
0answers
30 views

Finding or estimating sequential vs random distribution of existing system (VMware / SAN)

IOMeter testing says the IOPs of the storage subsystem can range from hundreds of IOPs for 100% random loads to tens of thousands IOPs for 100% sequential loads. Is there any way I can measure or ...
2
votes
1answer
421 views

How to cut php-fpm IOPS

I have Amazon EC2 instance with NGINX + PHP-FPM (through socket) + APC. I see sth. like this in iotop on high load. Total DISK READ: 0.00 B/s | Total DISK WRITE: 0.00 B/s TID PRIO ...
2
votes
1answer
114 views

“Hot data” and erasure coding: how to know if it is efficiently handled?

It is well known that erasure coding adds extra complexity because of encoding and decoding operations. Due to this drawback, most of cloud services recommend to use data replication for hot data and ...
1
vote
3answers
1k views

perfmon reporting higher IOPs than possible?

We created a monitoring report for IOPs on performance counters using Disk reads/sec and Disk writes/sec on four servers (physical boxes, no virtualization) that have 4x 15k 146GB SAS drives in RAID10 ...
1
vote
2answers
1k views

Limiting - IOPS in VMware causing servers to run VERY slow

I have servers running a few different iSCSI SAN units. I was trying to balance IO requests to the datastores, so I started changing the "Limit - IOPS" on my servers from unlimited to 100-400 ...
1
vote
2answers
300 views

Calculating IOPS for a single HDD - what am I doing wrong?

So I know there is no standardized way of calculating IOPS for a HDD, but from everything I have read it appears one of the most accurate formulas is the following: IOP/ms = + {rotational latency} +...
1
vote
2answers
7k views

How to interpret iozone values

I ran a test to measure my I/O IOPS on Linux: iozone -s 4g -r 2k -r 4k -r 8k -r 16k -r 32k -O -b /tmp/results.xls iozone claims that output is in operations per second yet the numbers are too big ...
1
vote
3answers
3k views

Throughput = BS * IOPS?

I've seen in many places that throughput = bs * iops should be true. For example writing at 128k block size to a SAS disk that can support 190 IOPS should give a throughput of ~23 MBps - 23.75(MBs) = ...
1
vote
3answers
635 views

Need the “msacli.exe” file for monitoring P2000 SAN. IOPS values needed

Hi i need some performance stats from our MSA p2000 SAN. The Problem is that i want to have the values i get when i connect via SSH and use the command "show vdisk-statistics". This command shows me ...
1
vote
1answer
686 views

IOPS write increased, Disk write latency decreased, Avg req size decreased - Page load speed decreased

I have noticed decrease in server performance (page load speed become lower), then I went to investigate and have found in munin graphs (which tracks server's resources) that there was big changes on ...
1
vote
1answer
407 views

PHP Websites: Very high IOPS

We are hosting a set of websites on VM Cloud. These sites were previously on a couple of dedicated servers but to enhance performance, we transferred them onto a Cloud environment. The Cloud has SSD ...
1
vote
1answer
77 views

Exchange 2013 reduce disk writes

I have some write problems on my system. One of the most ravenous virtual machine is Exchange 2013 with only 70 mailboxes. This is a writes list dump example: If we exclude all EDB files and ...
1
vote
1answer
89 views

The more threads the less IOPS?

I've just started trying out AWS. I have a Postgres micro instance on RDS and I'm running a crawler on a c4.large. When I have just one spider (one thread), I get about 10 write IOPS. but if two ...
1
vote
1answer
273 views

Tools for gathering metrics about physical environment for use in virtualization/cloud planning?

I'm looking for tools that will work on either Linux/Unix or Windows Server that for a given set of servers in an enterprise environent, will: Identify the server [via hostname, or some other unique ...
1
vote
1answer
2k views

How to I obtain details of current IOPs for an ESX Server

We have a number of ESX Servers connected to various iSCSI Targets and I want to do a consolidation exercise so want to get an idea of the current level of IOPS each of our servers uses. I tried ...
1
vote
0answers
25 views

XenServer 6.5 Zeroed Performance Metrics for IOPS

In one of my XenServer 6.5 pools, I'm adding some graphs in XenCenter to measure my iSCSI storage IOPS and throughput performance and I'm getting no response. The graph is actually responsive, but ...
1
vote
0answers
98 views

How to calculate current IOPS usage and IOPS credit count and graph on AWS RDS

I have a running Mysql db.m3.medium RDS instance at AWS, running with 20GB SSD as in: RDS machine description Last hour write and read operations went as following: Disk operations It looks like max(...
1
vote
0answers
89 views

Stress Test Hard Drive attached to a LSI controller on Hyper-V

I have a LSI 9265-8i controller running on Hyper-V. How can I stress-test the hard disks in-situ? I'd like to test things like iOPS, seek times etc.
1
vote
1answer
107 views

Many writes IO/s in Centos 6.5 - reverse ratio from read - as is normal

We have many CentOS6.5 servers on ESXI5.5. Storages for vmdk is SAN ISCI. I have problem with bad ratio for write/read. On storages I have about 2500 write io and e.g 200 read! For all time in day. ...
1
vote
1answer
2k views

interpreting IOPS these Bonnie++ and iostat results

I am looking to interpret the IOPS from a few runs of bonnie++ using iostat simultaneously and using the benchmarking from this post: Can I determine IOPS on a disk array using bonnie++? bonnie++ ...
1
vote
0answers
114 views

Upgrade the storage and/or provisioned IOPS on a reserved RDS instance?

I would like to reserve an RDS instance, but as of right now my instance does not need a lot of storage provisioned. I would like to reserve the instance with 100GB and 500 IOPS provisioned, but I ...
0
votes
1answer
584 views

IOPS bottleneck in design? [duplicate]

I'm building a 45 drives (backblaze) storage pod for use with Windows 2012 R2 Storage spaces. Spec is 2xE5-2620 v2 cpus, 32 GB ram, 3xLSI 9201-16i cards, 9x1 TB SATA SSDs, and 36x4TB HGST ultrastar ...