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

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7
votes
3answers
2k views

Apache on Win32: Slow Transfers of single, static files in HTTP, fast in HTTPS

I have a weird problem with Apache 2.2.15 on Windows 2000 Server SP4. Basically, I am trying to serve larger static files, images, videos etc. The download seems to be capped at around 550kB/s even ...
2
votes
2answers
29 views

Lots of major page faults in CentOS

We have a fairly complicated PHP script that's generating a lot of minor and major page faults. $> ps -o min_flt,maj_flt,time,cmd,pid 4686 MINFL MAJFL TIME CMD ...
0
votes
1answer
50 views

sudden peak in cpu usage

We are running a 4 node/machine elastic search cluster on 12 core, 96gb RAM, 4 spinning disk machines. under normal operation most cpu usage is user and around 5-10%. Every few days, one of the ...
0
votes
2answers
99 views

Debugging slow transfer rate from server

I'm trying to explain this as simple but documented as possible. This is not exclusive to this server or my current ISP. I've seen the same exact issue over the years while being with different ISPs ...
1
vote
1answer
43 views

MySQL suddenly taking 2000 ms per request, instead of 200

UPDATE: finally remembered to look at munin, and it seems that one of the HDDs is the root of the problem after all, unless I'm totally reading this wrong. Here's the munin output: ...
-1
votes
1answer
25 views

HDD performance testing over LAN [on hold]

Do you know some utility that allow me for HDD performance testing over lan. The issue - I have a shared drive with shared file database. Performance of the database is low and I assume that ...
1
vote
1answer
77 views

How can I diagnose and speed up slow Linux puppet sync?

I'm running puppet and it functions okay, but it's taking about 15 minutes on a sync without any changes, and it seems to me that this shouldn't take more than a minute or two. Here are some stats: ...
5
votes
6answers
2k views

For a small home network, is there any point to running Squid? [closed]

For a small home network -- two laptops, two desktops, plus the main server -- should I expect much gain by running Squid on the main server? I fully understand the value of running a caching name ...
1
vote
1answer
18 views

MongoDB - DB/collection fragmentation level

I recently had a performance issue with one of my collections. On a whim (and thanks to this article), I decided to try compacting (as written in the official documentation). This worked brilliantly. ...
0
votes
1answer
31 views

Is there anyway to find what php scripts consume more resources

I want to easily find load cause, Is there a way to display resource usage for php scripts like this. Cpu: index.php 30% something.php 10% ... memory: index.php 50% something.php 10% ..
0
votes
2answers
60 views

Unreasonable performance expectations for RAID 0 performance?

This is my first time building a machine with a hardware RAID card. We bought a Dell T620 with the H710P RAID controller (1GB NV Cache), a 160GB Solid State Drive (SATA Read Intensive MLC 3Gbps), and ...
3
votes
8answers
939 views

How to benchmark hosting provider?

I'm about to choose some hosting provider for my project. Is there any way to get information about speed of their servers, network speed? I think it would be very interesting to see such (average) ...
0
votes
0answers
12 views

Should I use mod_pagespeed for my websites performance? [closed]

Should I use mod_pagespeed for my websites performance. Is it good and secure to use it ? Or I should do all the performance stuff manually like CSS-JS minification and all code handling..
1
vote
1answer
126 views

upgrade/reinstall vmware vsan from beta

Being a VSAN beta tester I decided to upgrade to GA version as VMWare suggests for production sites. They say, it is not possible/supported to upgrade from beta to GA version, and I did not upgrade, ...
-3
votes
1answer
762 views

How to make high performance cluster out of 2 laptops I have at home [closed]

I have 2 laptops at home. Could someone please suggest some free cluster softwares using which I can make a HPC out of these 2 laptops so that when working on one of the laptop, I can use RAM,CPU of ...
0
votes
0answers
35 views

SQL Server 2014 Standard 2014 no access and bad preformance

My company looks after a server which is running SQL Server 2014 Standard Edition. The main application database on the server is replicated out to about 20 subscribers. The server has only been in ...
0
votes
0answers
19 views

CURL: Human-readable Transfer Speeds for FTP Uploads [on hold]

On Ubuntu 14.04, Curl produces human-unfriendly progress data during FTP uploads: % Total % Received % Xferd Average Speed Time Time Time Current Dload ...
2
votes
2answers
2k views

Testing SSL performance on Nginx

I'm running nginx 1.0.0 on CentOS 6 x86_64 with stock OpenSSL. Below are results of openssl benchmarking. sh# openssl speed aes-256-cbc OpenSSL 1.0.0-fips 29 Mar 2010 built on: Sat Jun 25 04:58:15 ...
0
votes
0answers
9 views

How do I determine what bandwidth/speed I will need for a website (I know page size, # users) [duplicate]

I am trying to determine the connection speed I would need for my website and monthly bandwidth needed. How do I do this? I know: # of users per month (I'm fine with using this number as a "fact") ...
0
votes
1answer
4k views

Performance Counter - % Disk Time and Avg. Disk Queue Length

% Disk Time - How often is the disk busy? If it's busy almost all of the time, and there is a large queue, the disk might be a bottleneck. This value is displayed as a percentage and is capped at ...
16
votes
3answers
12k views

limit linux background flush (dirty pages)

Background flushing in linux happens when either too much written data is pending (adjustable via /proc/sys/vm/dirty_background_ratio) or a timeout for pending writes is reached ...
1
vote
2answers
358 views

Apache2 BufferedLogs On - anybody using it?

Greetings, I am wondering, whether anybody is using BufferedLogs On with Apache2 and found any issues ? Feature is marked as experimental, but for many years now, so I guess it's rather pretty stable. ...
3
votes
1answer
861 views

How to improve Varnish performance?

We're experiencing a strange problem with our current Varnish configuration. 4x Web Servers (IIS 6.5 on Windows 2003 Server, each installed on a Intel(R) Xeon(R) CPU E5450 @ 3.00GHz Quad Core, 4GB ...
0
votes
1answer
23 views

Perfmon % Processor Time unbalanced

I am somewhat of an accidental DBA, and I'm troubleshooting a SQL Server box where performance has been notoriously poor (as reported by the customer). I was not involved in the initial planning of ...
43
votes
10answers
13k views

How to [politely?] tell software vendor they don't know what they're talking about

Not a technical question, but a valid one nonetheless. Scenario: HP ProLiant DL380 Gen 8 with 2 x 8-core Xeon E5-2667 CPUs and 256GB RAM running ESXi 5.5. Eight VMs for a given vendor's system. ...
5
votes
4answers
548 views

How do I configure RAID 5, especially stripe size, with 24 x 1.2 TB drives for CentOS 6?

For a Dell R920 with 24 x 1.2TB disks (and 1TB RAM), I'm looking to set up a RAID 5 configuration for fast IO. The server will be used to host KVM VMs that will be reading/writing files of all sizes, ...
0
votes
1answer
760 views

Performance Issue Between SQL and IIS on Seperate Machines

First time OP on serverfault, but an avid user of stackoverflow. We have two high-specification boxes, both running Windows Server 2008 R2 Standard. On one we have IIS 7.5, the other SQL Server 2008 ...
0
votes
2answers
39 views

Very high First Byte Time

A client of mine which I will be completely re-building the site for, is having some major speed issues with the current site. It takes on average 4.4 to 4.8 seconds before the First Byte Time to ...
0
votes
0answers
21 views

How to find out what is blocking requests on Apache2

I'm running a website on Apache 2.4.9 that creates thumbnails of images a lot and when users browse the website they create cca 100 requests per page. Thumbnails are returned by PHP script that has to ...
-1
votes
0answers
56 views

Reduce Nginx's response times

I'm running a VPS with 1GB with Debian 7. Nginx's response time for static HTML files are around 300-500ms, which seems relatively high, because other static files (CSS/JS) are served in 75-125ms. Is ...
10
votes
2answers
744 views

Why is my RAID1 read access slower than write access?

I have done some simple performance tests and it seems that reading from my RAID1 is slower than writing: root@dss0:~# for i in 1 2 3; do dd if=/dev/zero of=/dev/sda bs=1048576 count=131072; done ...
2
votes
1answer
33 views

What is the correct way to track and monitor Exchange DB replication “pressure” over time?

I want to determine if some databases are overloaded or unbalanced, and think that looking at the transaction logs created per database over time would tell me which DB is at risk of missing RPO ...
1
vote
3answers
255 views

VOIP and internet connection speeds [cable vs. fiber]

Our office is migrating to IP telephony. We have less than 10 employees that will be using the phones. We currently have cable internet, and they just bumped the speeds: There is a data center ...
1
vote
1answer
80 views

6 times slower disk write in RAID10 on Ubuntu 14.04 after rebuild

OS: Ubuntu 14.04 LTS Software Raid 10: 4x120Gb Intel 530 SSDs Initial tests: 1.2 GB/s Write 5.2 GB/s Read I did some tests to check if everything will go alright with a failed disk: I set as ...
0
votes
0answers
26 views

MySQL Workbench InnoDB Buffer Usage at 100%, always

The InnoDB Buffer Usage graph is always at 100%. I believe this started to happen when I changed MySQL's temp folder to a much bigger drive, does that make sense? I suppose the thing to do in this ...
2
votes
1answer
846 views

BackupExec 12 + RALUS - VERY slow backups

We use Backup Exec 12 and the Remote Agent for Linux/Unix Servers (RALUS) to backup a large RHEL5 system. For various reasons we need to do a daily working set job. These working-set jobs run ...
3
votes
1answer
162 views

Upstart: Why two processes when running as a different user?

I want to keep a nodejs app running, so I followed this: http://howtonode.org/deploying-node-upstart-monit and installed Monit and Upstart which have been working perfectly for a couple of months. I ...
12
votes
7answers
580 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 ...
0
votes
0answers
17 views

sar -b reports much too high statistics, are the I/O counted twice?

On a Linux server sar -b reports much too high read block statistics, sometimes 3.500.000 readb/s peak and around 2.500.000 readb/s sustain, which makes more that 1 gigabyte/s (according to the sar ...
0
votes
1answer
27 views

pagefile and disk space monitoring on server 2012

I have had a server crash recently because of the disk space. Here is what I have: a Hyper-V 2012 server with 1 win 2012 image physical disk is 500GB server uses 800GB It was OK for half a year but ...
2
votes
2answers
888 views

Changing memory allocator to Jemalloc Centos 6

After reading this blog post about the impact of memory allocators like jemalloc on highly threaded applications, I wanted to test things on a larger scale on some of our cluster of servers. We run ...
3
votes
1answer
62 views

Can rsync display current average speed?

When I'm transferring large quantities of data using rsync, it would be helpful if I could have the average speed up until now at a glance, rather than a bunch of different speeds for each file.
3
votes
2answers
235 views

Best practice on Linux servers and CPU/power throttling?

I am running a couple of Debian 6 (2.6.32) and 7 (3.2) Linux servers and all of them have energy saving settings enabled in their BIOS. Furthermore Linux shows that the CPUs are throttled if the ...
-4
votes
0answers
50 views

Make a WHM server handle 10k users at once [duplicate]

How do you get a Level 4, Media Temple Developer VPS, running WHM/Cpanel to handle 10k users at once? Our ole' HostGator Dedicated was able to handle it, but this one can't even handle 2k, probably ...
2
votes
2answers
704 views

How to delete unknown user profiles remotely?

When user is deleted from Active Directory, it shows as an unknown user. System properties -> Advanced -> User Profile -> Settings... I have to delete it manually all the time. There are more than ...
0
votes
1answer
19 views

Performance Monitor for ASP.Net applications

I have an IIS hosted ASP.Net site which is experiencing timeouts. I would like to be able to monitor it from every angle but I'm not sure where to start with configuring PerfMon counters. Does anyone ...
11
votes
6answers
15k views

How can I disable encryption on openssh?

I'm having performance problems using openshh(server) and putty(client) combination to use a remote webproxy. I'd like to disable encryption and test the results to see if it makes a difference. How ...
0
votes
0answers
111 views

Server 2012 slow performance on ESXi 5.5

I'm having performance issues with a virtual Server 2012 that is installed on an ESXi 5.5 (HP-ESXi-5.5.0-iso-5.71.3). The hardware server is an HP ProLiant DL380p Gen8. The server 2012 is acting as ...
3
votes
1answer
34 views

Optimal RAID10 configuration for 8 disks and two volumes?

I have an Open-E file server with 8 SAS disks and a MegaRAID 9271-8i controller and I want to configure two logical RAID10 volumes of identical size. One volume has about 66% write access and 33% read ...
2
votes
0answers
37 views

actual disk iops and write merging

/dev/sdb has LVM and exposes a single logical volume, dm-0. While writing to dm-0, /proc/diskstats reports: # of writes completed sdb 29646717 dm-0 131315099 # of writes merged: sdb 101668283 dm-0 ...