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Questions tagged [iops]

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2
votes
3answers
117 views

Is AWS i3.2xlarge limited to 10K IOPS?

I'm using an AWS i3.2xlarge EC2 instance and facing a limit of 10K IOPS. I wonder why that is? I only write on the NVMe instance storage. No matter what I do I can't pass that limit. I thought that ...
9
votes
1answer
140 views

what is the IOPS behavior when partitions of single disk are used in an LVM?

I have an ubuntu 14.04.1 LTS server which have LVM(backed by hardware RAID5) with logical volume and a volume group named "dbstore-lv" and "dbstore-vg" which have sdb1 sdb2 sdb3 created from same sdb ...
1
vote
1answer
270 views

Amazon RDS: Why do I get more IOPS than I have provisioned?

We run a Multi-AZ r4.2xlarge Mysql RDS instance and we provision 2000 IOPS (which costs $400 per month extra). When I check the CloudWatch charts I can see large periods where the Write IOPS are more ...
0
votes
0answers
187 views

MySQL RDS Write IOPS high

One of my client is having RDS MySQL DB for which write IOPS is high when compared to read IOPS. Tried increasing CPU and Memory to 8 and 61 GB respectively, but still it is the same. This is a small ...
0
votes
1answer
70 views

GCE Persistent SSD disks allocate more IOPS than specified

I've been testing GCE and created a VM with a persistent SSD disk to test disk performance. Persistent SSD disk that I configured was 37GB, which was supposed to give me 1110 IOPS but when I run ...
0
votes
0answers
35 views

Storage solution best practices for a VOD website with 5x servers at 3Gbps [duplicate]

I own a VOD website which serves mp4 files (each file-size varies between 100-2000MB). In order to serve VOD content I have 5 dedicated servers with the following hardware: Intel Xeon E5-2620 v3 ...
2
votes
1answer
150 views

Measuring Only Page Faults That Reach the Disk

I would like to measure "truly" hard page faults, i.e. page faults that result in a disk IO. It looks as if Memory\Page Reads/sec might do the trick, but as was explained in this answer, the page ...
1
vote
1answer
407 views

Performance Counters: Page Reads/sec higher than Disk Reads/sec

Comparing the values for the Windows performance counters Page Reads/sec and Disk Reads/sec I noticed that page reads are consistently higher, which is strange, as it seems that page reads should be a ...
1
vote
1answer
350 views

Low random read IOPS intel dc s4500

i have very bad read performance on my new intel ssd. My configuration is: HP proliant DL360e gen8 with Smart Array P222 controler. Intel ssd dc s4500 960GB 64GB ram 2x Intel cpu I have 2x SAS HDD ...
0
votes
1answer
108 views

SSD Raid perfomance

Disks: 10xSSD Ultrastar SS200 960GB 12GB/s Raid 0, 6, 10. Controller: LSI Syncro 9380-8e Filesystem: ext4 without LVM System: Centos 7 2x E5620 @ 2.40GHz 32GB RAM fio-2.1.10: --iodepth=32 --ioengine=...
0
votes
0answers
25 views

IOPS - Is the speed calculated as the combined read and write speed or one or the other

When a disk is said to have 20,000 read/write IOPS speed, does that mean the IOPS speeds for the disk is 20,000 as it can read and write at 20,000, or does it mean the total IOPS speed is 40,000? In ...
1
vote
2answers
175 views

PerfMon within a VMware 6.5 VM in 2017: Accurate?

Looking to measure the performance of a VM over a two-week period, which means the Performance tab in vSphere client/UI is not really feasible. esxitop appears to only track the host, not a ...
0
votes
2answers
71 views

Is there a better way to handle 100-200+ files/s?

I’ve got a challenge that as it stands right now, is hitting limitations of cloud computing in terms of IOPS and CPU. The thought is to bring these systems in-house long term but I think it can be ...
9
votes
2answers
3k views

Impact of RAID levels on IOPS [closed]

With regard to IOPS, I have seen several sources on the web that suggest the IOPS of a given number of disks is simply the IOPS of a single disk multiplied by the number of disks. If my understanding ...
1
vote
0answers
226 views

How can I measure RAM/tmpfs IOPS from a specific application?

I am running a hadoop-based application (hadoop 1.2.1), where I had discovered a hard-disk bottleneck; monitoring the hard disk IOPS with iotop resulted in ~160 MB/sec, which was the writing speed I ...
4
votes
0answers
1k views

Better performance when HDD write cache is disabled? (HGST Ultrastar 7K6000 and Media Cache behavior)

Attention, please. Long read. During initial performance tests of Hitachi Ultrastar 7K6000 drives that I'm planning to use in my Ceph setup I've noticed a strange thing: write performance is better ...
2
votes
1answer
90 views

Microsoft performance monitor counter - Disk activity & file

I'm looking for a way to quickly (via PowerShell Get-Counter) show me the I/O load (IOPS preferable to bytes) on a certain physical disk, along with the file access information - presumably the file ...
1
vote
1answer
284 views

IOPS super low after creating volume from snapshot (AWS)

I'm using EC2 p2.xlarge instances to train an image processing model. My target classes for the prediction task are quite a few (20) and to get the best accuracy I'm going to train one model per ...
1
vote
1answer
1k views

Strange IOPS performance on AWS R3.large & R4.large instances

I have used 4 10GB GP2 EBS volumes with RAID0 on Windows Server 2012R2 image as explained here: http://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/raid-config.html The instance type I used was R3....
0
votes
1answer
674 views

php-fpm with NGINX response time exponentially increase over time

I have a load balanced application on AWS, on two c4.2xlarge (8 vCPUs, 15GB ram) servers and they serve a very simplistic site but with a system call to ffmpeg encode a <5s mp4. Individually, the ...
31
votes
8answers
8k views

Why do IOPS matter?

I understand what IOPS and throughput are. Throughput measures data flow as MB/s and IOPS says how many I/O operations are happening per second. What I don't understand is why many storage services ...
1
vote
0answers
95 views

AWS EC2 snapshot reaches IOPS limit occasionally

For an EC2 server I have running I am creating a snapshot of the EBS every night. The EBS has 500GB of space and 1500 / 3000 IOPS. On some days past week the snapshot creating process reached it ...
5
votes
2answers
611 views

Get an AWS EC2 ebs volume to perform over 20,000 IOPS

The company I work for is currently going through an AWS migration, and for 99% of services, their commodity hardware does the job just fine. Except for the production Database, we currently sit at ...
0
votes
0answers
215 views

The fio shows iops very less for CentOS6.0 vm running in kvm with backend disk SSD

Disk "iops" is very less with "fio" disk benchmark tool for CentOS 6.0 virtual machine running on KVM. When I execute same on CentOS 6.7 and CentOS 7.2, the iops is as expected. The back end disk is ...
4
votes
1answer
177 views

Terrible (~1.4x vs expected ~2x) random read performance in new ZFS mirror (raid1)

I am testing a ZFS mirror using FIO (Flexible I/O tester) to understand the random read scalability of ZFS mirrors. The primary and secondary caches have been set to none as the application I use ...
1
vote
1answer
582 views

IOPs Comparison and Block Size

As long as I know - IOps is a IO operations per second on a given data block. But size of that given block if often omitted. I assume, that block size does not make difference as long as its ...
-3
votes
1answer
170 views

How to configure Fio to a more accurate result of IOPs

I am using fio to test how much iops my server can offer. My conf file says to write a 20GB file and read it. THe results show iops=27291. But the test last only 10 seconds. I wonder if the test last ...
0
votes
0answers
46 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
82 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
37 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
83 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
923 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 ...
3
votes
0answers
141 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 ...
4
votes
3answers
3k 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
174 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
631 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 exchange ...
0
votes
1answer
347 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
3answers
2k 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
83 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
votes
1answer
1k 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 ...
3
votes
0answers
151 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
2k 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
125 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
1k 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 ...
5
votes
1answer
1k 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 ...
5
votes
1answer
3k 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 ...
3
votes
1answer
201 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 ...
0
votes
1answer
2k 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
4k 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
vote
2answers
3k 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 ...