Questions about server hardware and software performance, or network performance.

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2
votes
2answers
47 views

Performance tuning world wide?

I am working on a website that is used by people all over the world. Currently we have a web server that is in Oregon and a database sever that is in Chicago. When users from the US access the ...
3
votes
5answers
285 views

Router limits network performance but its CPU load isn't 100%

I'm using a PC Engines APU device running FreeBSD as a NAT router. The setup is very usual: one WAN connection and one LAN connection. Theoretically, WAN connection is 800/40 Mbit/s and the LAN one ...
2
votes
2answers
102 views

Virtualized Server 2003 vs Server 2008 R2 file transfer rate differences?

Basically I am trying to find out where the difference in the rate of a network file copy might come from. I have a virtual Server 2008 R2 SP1 and a virtual Server 2003 R2 SP2, using the same store, ...
0
votes
0answers
88 views

Windows Server 2012R2 benchmark [duplicate]

i hope you can help me. I have got this task to "characterize" and benchmark performance on our new server setup we have at a hosting center. Basically it is 2 HP ProLiant DL380p Gen8, 3.00 GHz, ...
1
vote
0answers
42 views

Performance issues with cross-drive NTFS junctions

I have the following setup: Windows 8.1 32-bit Drive 0: system drive, SSD, NTFS, mounted at C:\ Drive 1: data drive, magnetic HDD, NTFS, mounted at C:\Users\Database User\Documents and Z:\ ...
0
votes
0answers
43 views

How efficient is the tac command on large files

The taccommand (catreversed) can be used to read a file backwards, just like cat reads it rom the beginning. I wonder, how efficient this is. Does it have to read the whole file from the beginning and ...
0
votes
0answers
37 views

MongoDB hogging IO but it doesn't show in mongotop or mongostat

Iotop says mongod is using a lot of IO (96.32%) for a long while but mongotop and mongostat show a bunch of zeros. How can I better monitor mongodb and find out what's happening?
1
vote
2answers
145 views

Slow serving of static files with IIS 8

We're hosting an ASP.Net MVC web app on Windows Server 2012, which runs over HTTPS. Most of the time everything is nice and fast, but we've noticed that about 1 in 50 requests for static files (e.g. ...
1
vote
0answers
63 views

finding if my linux server is the bottleneck

I have a redhat linux 6.x server being used for writing of backup images by NetBackup before being dedup to tape library. currently, I have at least 20 servers writing to it every time their backup ...
0
votes
0answers
42 views

Counterintuitive drop in CPU

I am running a memcached service in a linux container pinned to a specific physical core. As expected the CPU increases when the number of requests increase. The requests are sent from a workload ...
1
vote
1answer
26 views

Does it make sense to remove NFS from a simple web server?

Does it make sense security- and performance-wise to remove NFS on a simple server which has ~10 Wordpress websites? Or is simply stopping the services enough?
2
votes
1answer
55 views

Parallel Processing and Disk IO for performance. More cores or more servers?

I have a large analysis job on an AWS EC2 instance (c3.8xlarge) on Ubuntu 12.04. The objective is to load the server at 100% CPU, running as many jobs as memory allows (varying amounts but generally ...
1
vote
1answer
157 views

How to determine performance improvement from precompiling ASP.NET site?

I have an ASP.NET (non-MVC) site that is deployed to IIS. I've setup the precompile options (for deploy/publish). Settings are below in the image. I've tried a variation of the settings below and from ...
0
votes
0answers
57 views

Strange performance issues on CentOS KVM guests

I have a very basic hypervisor server. It is based on consumer hardware and does have some quirks, so I'm not excluding hardware issues. Guests on this machine have strange performance issues, it ...
1
vote
1answer
95 views

Linux fixed file size copy from Windows Server 2012 NFS share

Company is in the process of switching from hosting MongoDB on windows server 2012 to hosting on linux(ubuntu 14.04) Current backup and restore strategy involves copying all the data files via ...
4
votes
2answers
923 views

Which CentOS Version Should I Use?

I have some used rackmount servers (Dell R610, HP DL180 G6, HP DL360 G5) that I intend to use for on demand video streaming in a colocation environment. I would like to have them all on the same OS to ...
0
votes
0answers
22 views

Troubleshooting Rails 3 application performance problems

We deployed some apps upgraded to Ruby 1.8.7, Rails 3.1.11 on Dec. 30 (i know, we're in perpetual upgrade mode, targetting Ruby 1.9.x now..). One of the apps' performance has been poor since then, ...
2
votes
2answers
426 views

What does RXTX Factor mean, what is it and how does it affect my server?

In the Rackspace overview for their next gen servers they have a table of flavor options. In the table there is a column called RXTX factor with no explanation. I tried googling, but couldn't find ...
0
votes
1answer
38 views

Measuring request response time by port

So, I'm currently working on a project in which I spin up a set docker image on a number of different machines and configurations. This image basically contains a web server that accepts a number of ...
0
votes
0answers
103 views

Python libraries slow to load from NFS mount point

Several of our computers are diskless, and they load their Python libraries from an NFS mount point across the network. This means it can take up to three minutes to start up a Python process that ...
4
votes
1answer
86 views

psping to localhost - improve throughput

I'm using following psping command to measure the bandwith throughput for localhost on a physical server psping -4 -b -l 8k -n 20000 localhost:1234 The throughput is around 150MB/s wich isn't all ...
1
vote
1answer
385 views

ssd performance against hdd performance

I have two server, one with a SSD, one with a HDD. I've been running hdparm to see the differences, but the results for Timing cached reads and Timing are quite equal/HDD is faster: SSD: Timing ...
0
votes
2answers
92 views

TCP - TAP performance

Linux. Is there a performance loss from using a tap device vs a hardware one like eth0 ? The goal is to create a user space tcp/ip stack and avoid the kernel as much as possible. I would like to be ...
0
votes
0answers
36 views

Performance Monitor Single W3WP

How to set my counters in perfmon to track a single W3WP process?
1
vote
2answers
146 views

Performance Tuning Linux [closed]

Performance Tuning/ Monitoring/Latency keeping in mind I see following 4 items & in each item they are lot of tools. CPU Memory IO Network What I see following tools we do use. vmstat mpstat ...
0
votes
1answer
93 views

UFS wedge : “Out of journal space!” - how to tune? (FreeBSD)

I'm running FreeBSD 9.2p13 with UFS and journaled softupdates. Does anybody know how to tune softupdates journal on UFS? There are no suitable information in handbook, man pages or sysctl ...
2
votes
1answer
161 views

Azure IO performance sql server [duplicate]

We are in the process of migrating our on-premises sql server to Azure and I am having trouble with the IO performance. I have created a new D14 instance and attached 16 virtual disks at 100GB in ...
1
vote
1answer
285 views

Apache CentOS Server very slow! Wrong configuration?

I have a problem with server overload on a Apache configuration 8gb of RAM 1and1.com Virtual Server. Server gets extremely slow once it reaches 100+ active users (according to google analytics) during ...
0
votes
0answers
115 views

Packet loss between windows guest and Ubuntu 14.04 host

We are seeing packet loss between one of our Ubuntu 14.04 hosts and a KVM guest running Windows 2008 R2. The loss only shows up at high loads. Similarly loaded machines running 12.04 do not exhibit ...
1
vote
1answer
58 views

Read performance of old LTO-2 tape

I have a stack of old LTO-2 tapes, and my task is to save the contents as large binary files on disk for eventual consolidation on newer media. (The contents are in a custom format specific to this ...
0
votes
1answer
151 views

Improve openvpn bandwidth Debian 7

I configured openvpn on a dedicated server. Things are working fine but the bandwidth is not as high as it should be given the network specifications : The dedicated server has 250Mbps DL speed and ...
2
votes
2answers
88 views

How can I speed up PowerShell cmdlets that are using the -CimSession parameter?

As the title says, how could someone speed up the execution of this tiny script? Am I using the New-CimSession that right way anyway? $computers = Get-ADComputer -SearchBase ...
-1
votes
2answers
68 views

Parallel disk seek with JBOD

I'm looking to build a 80 TB file based storage system. Ideally, I'd like to do this with a large JBOD and one server with a lot of cores. My question is: Will JBOD containers (like Intel's) allow ...
1
vote
1answer
112 views

Tuning Linux TCP for large number of TIME_WAIT

It looks like we have a bunch of tcp connections hanging around on a busy webserver, this is the output from ss -s: Total: 366 (kernel 1037) TCP: 72108 (estab 130, closed 71964, orphaned 0, synrecv ...
17
votes
2answers
1k views

How are CPU time and CPU usage the same?

In the Wikipedia page for CPU time, it says The CPU time is measured in clock ticks or seconds. Often, it is useful to measure CPU time as a percentage of the CPU's capacity, which is called ...
2
votes
1answer
51 views

Performance-wise, is a DNS Slave better to have than two duplicate Masters?

I have two bind9 servers that are not setup with duplicate settings and know nothing about each other. Our CPU usage is sitting around 7% - 10%: mostly bind, which I believe is perfectly in range for ...
0
votes
1answer
108 views

Why is Win Server 2012 slow to read data with RAID 5?

We have new HP 350p server with 4x 900GB 10k SAS disks with RAID 5 (win server 2012). But disks performance to read data is to slow - it's to slow to read big directory structure on disk. Where can be ...
1
vote
1answer
29 views

slow file server with contradictory values for CPU and CPL in atop

I've got a fileserver (centos 6.3) that slowed down suddenly earlier today. The cluster that mounts it could access other NFS mounts without a problem, but the access to this one was VERY slow. ...
1
vote
0answers
152 views

NGINX using 100% of the server CPU when testing with Blitz.io

I'm facing an issue here and after four days of looking around I decided to ask for some help here, after all a million heads can think a lot better than one. I have a Ubuntu 14.04 server setup with ...
1
vote
1answer
53 views

Strange Disk Benchmarking results for our storage, how to explain? [closed]

I recently tested the storage we got from our hosting provider. I don't know what raid config or how many disks the storage contains of. I used Atto Disk Benchmark which sends smaller and bigger ...
1
vote
0answers
26 views

Improve read performance on ext4 on Centos with software raid1? [duplicate]

I'm running a number of MongoDB nodes on dedicated servers running Centos6. Each machine has two SSDs which I have in Raid1 with two logical partitions: # df -h Filesystem Size Used Avail Use% ...
1
vote
2answers
45 views

What is the difference between truss -D and truss -E?

I am currently analyzing a command on Solaris that reads from a file and has very low performance. The truss -D commands shows me read system calls taking up to 0.03 seconds, but when I use truss -E, ...
1
vote
1answer
485 views

Ubuntu Server 14.04LTS Swappiness for server with 16GB memory

(don't worry I'm not asking what my setting should be, asking for the theory behind some conflicting advice I've read) My application is one that is lightweight and not under much load, but needs to ...
-2
votes
2answers
387 views

fastest way to transfer small files (faster than scp) [closed]

Scp is quite slow for transferring individual files. What is the quickest way to do this? The reason I need speed is not because I have a large number of files to transfer. I just want the individual ...
0
votes
1answer
147 views

What is the counter type for Linux's /sys/block/$DEVICE/stat

What are the counter types for /sys/block/$DEVICE/stat? $ cat /sys/block/sda/stat 8323741 42381356 464031898 19207478 1940738 49062039 408122282 79935459 0 22315734 99172579 Specifically, ...
1
vote
1answer
153 views

Website performance sluggish - High CPU and Disk Usage

Over the past couple of days my website's performance has been very sluggish, with queries taking a lot of time to execute. My CPU usage hit around 100% 4 times this week. Here is the output of top at ...
0
votes
1answer
95 views

PostgreSQL queries slower than before?

I am using PostgreSQL 9.3 server on my production server. Everything had been working fine for the past couple of months. But since the past week or so, PostgreSQL seems to have becomes very slow with ...
0
votes
1answer
72 views

Measure Dedicated Server Performance

I run an online video streaming site and keep getting more and more dedicated servers. Our business traffic fluctuates on an annual cycle which allows us to scale back our dedicated servers during the ...
0
votes
0answers
74 views

What happens on an SQL Server when a snapshot is taken by VMWare?

Recently I saw in our SQL Server logs that a snapshot could not be taken at the specific time and he retried it later on. During that timespan we had a huge performance problem. Besides the SQL Server ...
0
votes
1answer
683 views

How to solve performance problems with VMware ESXi 5.5 on old Dell PowerEdge 2900 hardware [closed]

I have a couple of old Dell PowerEdge 2900 servers that have come free and I would like to use them to host a mail server cluster. They are a bit old, but have been running workhorses for a while, ...