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0
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0answers
34 views

RAID 5, 50 or 10 with HOT SPARE Possible…? [duplicate]

I want to go for a Larger storage capacity but getting confused to use RAID Level. As have to reach the required IOPS, still maintain reasonable redundancy and have at least 5TB of logical storage ...
0
votes
0answers
19 views

why IO/sec has the value smaller than 1?

I do not understand why the value of IO/sec is < 1? For example, the output of "iostat -x" is as below. The r/s or w/s of sda is 0.06 or 0.95. My question is the IO is an action to do read or ...
0
votes
1answer
31 views

Drop in write performance when mirroring two RAID 0 arrays

On a CentOS 7 server with 4 SSDs, I created two RAID 0 arrays with mdadm. Both were formatted with ext4 and mounted on separate directories. I benchmarked them using fio and got the following results ...
0
votes
1answer
26 views

Purposefully overloading iops?

I was going to run a test with some of my junior devs on a few of our boxes and have them troubleshoot an "Out of IOPS" issue. I am curious if there is a way to purposefully overload or create an out ...
1
vote
0answers
29 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 ...
2
votes
1answer
45 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 ...
3
votes
1answer
111 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(...
0
votes
1answer
32 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
vote
1answer
95 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
votes
1answer
100 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
votes
2answers
183 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
votes
1answer
35 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 ...
0
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0answers
242 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
403 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 ...
1
vote
0answers
90 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
3answers
693 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
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 ...
2
votes
1answer
620 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
505 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
2k 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
116 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
491 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. ...
1
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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 ...
0
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2answers
154 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 ...
12
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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 ...
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. ...
0
votes
1answer
593 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 ...
-2
votes
1answer
157 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 'em...done...done......
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 wchar:...
6
votes
1answer
10k 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
votes
2answers
133 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
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
115 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
236 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
542 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 + ...
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 ...
1
vote
2answers
303 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
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) ...
-1
votes
2answers
235 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
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++...
6
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 ...
1
vote
1answer
688 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
409 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
859 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
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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 ...