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36 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 ...
0
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1answer
21 views

Low iops,read and write performances

We are currently testing our using ZFS on Linux as a storage platform for our VPS nodes but we don't seem to be getting the performance figures we expected. Can you please provide some suggestions as ...
1
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1answer
27 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 ...
0
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1answer
43 views

How to get live scsi traces from Vscsistats?

Here are things I already know, using vscsistat -t option I can get command traces for "VM/.vmdk" on ESxi. Steps to get scsi traces are: Start capturing traces, On Successful starting will ...
0
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2answers
77 views

Is our RDS write IOPS too high

Our site has been running slow recently and I've noticed that the RDS write IOPS can go as high as 80/sec and as low as 9/sec. Is this something that could be causing pages to load slowly? If so ...
0
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1answer
21 views

Improving high IOps Folder (Tomcat and Vmware)

Good day. We're moving a Tomcat from a physical server to one virtual Server. In the physical, and because the high IOps for the temp folder (¡developers!) we bought a Ramdisk software. My question ...
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0answers
151 views

LINUX fio random read write Total BW and IOPS calcluation

My fio ouptut for random readwrite is as shown below. Fio was initiated with 3 numjobs fio --name=test_random_read_write --iodepth=16 --rw=readwrite --bsrange=4k-8k --direct=1 --size=2G --numjobs=3 ...
0
votes
1answer
209 views

Finding correct IOPS to set limit with ESXi 5.5u2 and vSphere

We're running an ESXi 5.5u2 hypervisor that has a mirror of 2 15k SAS drives with a couple of VMs inside and we noticed some services become briefly unreachable if another VM is using all the IO. So ...
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0answers
80 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.
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3answers
363 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
78 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 ...
2
votes
1answer
536 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 ...
4
votes
1answer
432 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 ...
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 ...
2
votes
1answer
102 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
votes
1answer
316 views

How to specify the path which is to be tested using iozone?

I have a freebsd install which has ufs filesystem. Inside freebsd i have created a zpool in raidz1. Now i want to perform iozone test on zfs but i am not able to understand how to specify that iozone ...
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. ...
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2answers
893 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 ...
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2answers
132 views

Measuring disk usage

What is the fairest unit to determine the disk usage (except the total storage usage e.g. in GB)? IOPS? Bytes read / write? Bytes transferred over network (would be equal to Bytes r/w)? Other? And ...
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7answers
5k 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 ...
1
vote
1answer
106 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. ...
0
votes
1answer
519 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 ...
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1answer
144 views

less IOPS number but better READ/ WRite performance [closed]

I tried measuring virtual disk performance using bonnie++. Case 1 result : Using uid:0, gid:0. Writing intelligently...done Rewriting...done Reading intelligently...done start ...
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
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 ...
4
votes
1answer
8k 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 ...
0
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2answers
118 views

IOPs usage In HP Fata Disk Group VMware 5.1

We have a Blade with EVA storage array with 3 disk groups. One disk group consists of FATA 7200 1TB 18 hard drives, RAID 5, total IOPs 1000-1300. And I get statistics of used IOPs for this disk group ...
1
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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
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0answers
112 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 ...
-1
votes
1answer
214 views

How to test is hardware ssd-cache work?

We have server with hardware raid controller (Adaptec ASR71605Q). It has 10 sas HDD, 2 SSD for cache and 1gb onboard cache ram. On server installed ESXi. On ESXi I'm start Linux, create 2Tb disk for ...
4
votes
1answer
505 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
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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 + ...
6
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2answers
7k 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 ...
1
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2answers
253 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} ...
4
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1answer
6k 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) ...
-1
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2answers
222 views

Raid0 IOPS poor performance [closed]

I've set up 8x500gb disks in raid0 on an EBS optimized EC2 instance and I ran iops.py to check the speed, but it seems really slow. Does anyone know if this is normal speeds for raid0? I'd think I'd ...
6
votes
2answers
5k 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 ...
4
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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 ...
1
vote
1answer
655 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 ...
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 ...
1
vote
1answer
380 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 ...
2
votes
2answers
806 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 ...
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 ...
2
votes
1answer
388 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 ...
3
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2answers
2k 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 ...
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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) = ...
0
votes
1answer
2k views

Measuring IOPs and comparing with IOmeter

So I've got to somehow generate IOPs using some prehistoric metrics used in IOmeter (which can't run in a 64bit ubuntu environment) The settings used in IOmeter are: 16K block size, 75% read to 25% ...
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3answers
21k views

How to measure IOps one virtual machine on VMWare ESX?

How should I measure IOPS generated by a single Virtual Machine in VMWare ESX? Also what would be a normal amount of IOPS for a Windows XP virtual machine?
2
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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 ...
1
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1answer
261 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 ...