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

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0
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0answers
9 views

Force disk cache even if guest uses direct i/o

Have IBM db2 on Rhel on Hyper-V on Windows Server. The *.vhdx file is on CSV. e.g. C:\ClusterStorage\volume1\hyper-v\oktest-lb1\oktest-lb1.vhdx. db2 uses O_DIRECT flag (uncached i/o) for its database ...
1
vote
1answer
30 views

Different network speeds from servers on same subnet

I have a pretty strange issue, I'm looking for advice on how I can debug it. I have two servers (A) and (B) on the same subnet and switch. Server A->B transfers at a full 12MB/s and vice-versa. ...
1
vote
0answers
22 views

How to track down bad performance on an api-server

If my api-server shows bad performance, such as high cpu - can this be blamed on the service or on the server? If a regular app-server shows bad performance, all I can do is track down the methods ...
-3
votes
0answers
43 views

Why is giga bit network fast than disk? [on hold]

Why is fast giga bit network than disk? According to below URL for slide of Dr Jeff Dean, giga bit network is fast than disk. ...
0
votes
0answers
21 views

SSD vs RAM - Optimal ratio for different data sets / databases [duplicate]

I am looking for an advice or even better some studies / benchmarks to read for different scenarios (data sets) when it comes to the best ratio between actual RAM and SSDs. I know that fitting the ...
1
vote
1answer
65 views

ZFS reads on FreeBSD incredibly slow

I have a FreeBSD 10.0 system on which I have MySQL running with its InnoDB database files stored on ZFS. It seemed to have been going fine for months, but lately, and seemingly suddenly, performance ...
0
votes
0answers
21 views

vSphere | VMs are balooning and swapping | sched.mem.max paratmetar does not exist

I have two VMs in ESXi5.5 environment that are swapping memory. After a long research I found out the below two articles where it is explained that one must compare the values of memsize and ...
0
votes
0answers
11 views

How can I adjust buffer settings when using xbootmgr?

I am trying to analyze our clients which suffer from long boot & logon delays, so I installed Windows Performance Toolkit. This is the command line I have used to capture a startup: xbootmgr ...
-2
votes
0answers
18 views

NGNIX server for static content is too slow

I'm new to NGNIX server. Perhaps someone can help me to solve the issue. Here is my server configuration file: server { listen 80; server_name static.myhost.com; access_log ...
0
votes
0answers
15 views

How to estimate max request per second of web servers? [duplicate]

I'm planning on a system that handles quite a huge amount of requests per second (say 500,000 requests / second). How to estimate maximum request per second of my web server can handle (so that I can ...
2
votes
2answers
34 views

Migrating Vmware to Hyper-V - number of Virtual CPU

I'm performing a migration from VmWare to Hyper-V and the Virtual CPU that you are assigning to a Virtual Machine is different and I'd like to know what should be the equivalent values when we move a ...
0
votes
1answer
28 views

Sata Disk very poor performance

I have a HP MicroServer NL54, stock BIOS, with 4 HDs Seagate Barracuda ST2000DM001 2TB 7200 RPM 64MB Cache. If I run a dd benchmark I get: $ dd if=/dev/zero of=/dev/sdb bs=4K count=4096 4096+0 ...
-2
votes
1answer
40 views

Servers in different DC's - performance impact

Today Linode eat my nerves completely by shutting down main DB server for 25 minutes due to their internal network problems. Right today I was going to set up another one server at linode to set up ...
0
votes
1answer
16 views

HP ProLiant BL460c Configuring Memory

I hope you can help me. I need to install 48GB of RAM in an HP BL460c G1. The CPU is 48W, and I've researched the specification and I can do it for this kind of processor. I've also read the basic ...
0
votes
0answers
18 views

KVM Virtual Machines and Public IPs

I currently have some Virtual Machines on my business dedicated server using the KVM layer as apposed to Xen or other virtualization methods. I was wondering if I could get a "best practice" on ...
-1
votes
0answers
22 views

Hardware limitations of a RADIUS server? [duplicate]

I would like to configure a RADIUS server to authenticate users by retrieving informations from an HSS. However, I am wondering about the need to install several servers with a load balancer. Note ...
-1
votes
4answers
70 views

MYSQL - is LOCALHOST speedy than i.e. (domain) mysql.domain.com [closed]

I am interested, on some hosting(although they are paid hostings, for example, DreamHost. probably 000webhost too), in database server, you have to insert: mysql.domain.com (instead of: localhost). I ...
2
votes
0answers
25 views

NGINX Worker Process, Burst Read Speed to only 1918kb/s

I am running an NGINX/1.8 server on Centos6.6 with multiple worker_processes, however while observing iotop I notice they burst up to 1918kb/s Read speed and rarely if at all pass that limit. I want ...
3
votes
2answers
108 views

NGINX Serving Large mp4 Files extremely inefficiently

I am currently running nginx/1.0.15 on a Centos 6.6 OS. The server has the following specs: Intel(R) Atom(TM) CPU C2750 @ 2.40GHz (8 cores) 32GB Ram 5 x 6000 GB 7200 RPM (Raid 10) The Problem The ...
1
vote
1answer
34 views

postfix SMTP outgoing gateway server, Software RAID1 vs RAID1 + RAID 0 on 2 disks

I have this old smtp server that is currently running Windows 2003 and with EOL I want to move it to something that will continue to get security upgrades but at same time I want to improve ...
-1
votes
0answers
27 views

Database server: E5-2620v2 MLC SSD Software RAID1 vs E5-2650 Hardware RAID 10 / 2X RAID 1 for read performance and reliability [duplicate]

I am looking for a new database server and I have 2 options at this point with multiple configurations, all assuming same price. This will be a PostgreSQL database server with lots of READ (we are ...
-2
votes
0answers
15 views

What is the key point to select Server for Database vs Server for Website [duplicate]

I would like to know, what is the key point to select between Server to used for Database (ex. used for store all data, select / insert / update all transaction) Server to used for Website (ex. ...
0
votes
1answer
32 views

MySQL slow connection

I am running a laravel application that is on a separate server than my MySQL database. If I run the query on the Mysql server it takes the expected 0.00 - 0.01 seconds to return. However when I log ...
1
vote
1answer
26 views

Use in-memory database or search engine for read only to make website faster

I have an application which require doing a lot of queries for every single page which make it slower. I have tried to use cache systems (Redis) but implementation are little bit complicated and will ...
1
vote
1answer
41 views

nginx loading page very slow

I just deployed nginx in a new environment with the same configuration that I've used previously and I am seeing some very odd behavior. Nginx is configured as a reverse proxy for Solr, when I try ...
3
votes
1answer
64 views

How to find source of system running slow clock?

I've a problem on one of my Gentoo server. After some time, the clock starts running very very slow. It takes about one minute for one second to go. The major problem is that not only the clock is ...
2
votes
1answer
47 views

cloud server performance vs same specification dedicated server?

I have a web application written in php (5.6.10) and using Postgresql (9.4) we have about 4k users per day and about 20k page views per days, my main issue that we are running in cloud host with 2 ...
5
votes
2answers
155 views

cpufreq-info differs from /proc/cpuinfo?

I have a server and I want to ensure it's always running at maximum speed, never in energy-saving mode. I've tried a few strategies (aside from rebooting and changing the setting in the bios, which I ...
3
votes
2answers
66 views

Performance azure disks, high average queue length

I'm having a classic developer-system admin battle where I am stating that there is an IO problem on the disk of the shared sql server while the system admin tells me that the capacity hasn't been ...
1
vote
2answers
62 views

PHP5-FPM pm.max_children affect RAM or CPU+RAM?

Recently inherited a Nginx+PHP5-FPM server, and I'm learning and trying to optimize PHP5-FPM settings. Server info: 4 CPUs (8 threads) 7.5 GiB RAM PHP5-FPM info: pm.max_children = 5 ...
0
votes
0answers
4 views

Large TTFB on Vagrant [migrated]

I have a ttfb of approximately 15-20 seconds on a VVV vagrant install. I am using virtual box on windows 7 in case that makes any difference. I have tried reprovisioning and also tried increasing the ...
-2
votes
2answers
67 views

Is it normal to have 400~600ms of waiting for first byte? [closed]

I have optimized my website and apply many advices found on the Google search. but finally i have about 400~600ms of time to first byte. Does it normal or I can lower it? For dynamic data it it about ...
1
vote
0answers
31 views

Nginx: Optimal map_hash_max_size and map_hash_bucket_size for 1M map?

I have 1M static rewrite rules and using this map configuration. How to determine the optimal values for map_hash_max_size and map_hash_bucket_size? I want to optimize for memory consumption. The ...
1
vote
1answer
36 views

nginx no speed limitation for a connection

I have a server with nginx installed on it to serve some files for downloading. I also didn't change default configuration of nginx. Problem is that when I try to download from this server it seems ...
-1
votes
0answers
15 views

Calculating concurrent connections for web server

I have few servers running behind an IP address which is serving https connections. I have measured the connection latency to be 4 secs. If I say my system can handle 100TPS then is it possible to ...
0
votes
0answers
36 views

Slow FTP download speeds on Synology DiskStation

We just got a Synology DS2415+ NAS which is connected to internet via a FIOS 300/300mbps connection. I am testing download speeds from a remote location with a 200mbps download connection. When ...
1
vote
0answers
20 views

IIS hanging when running Active Reports, possibly splwow64.exe

We have a Windows 2008 R2 web server running our web app on IIS and when running a particular page which generates a PDF (using Active Reports https://activereports.grapecity.com/) it takes between 1 ...
3
votes
1answer
76 views

NFSv3 client differences in read/write performance

I'm taking care of a few servers that make relatively heavy use of a NFS filer. At crunch time a single server sends about 2k reads + 2k writes per sec to the filer. According to nfsiostat at these ...
1
vote
1answer
70 views

Unexpected File Download Slowness After Enabled SPDY on Nginx

A simple WordPress static site run entirely on https. Nginx conf here: http://pastebin.com/BrP0LThT Only difference before / after is: listen 443 ssl; listen 443 ssl spdy; Nginx ...
1
vote
0answers
14 views

What is involved in adding ZFS cache stats to orca?

I am interested in looking to add ZFS cache stats into existing orca performance monitoring that we have. Particularly, I am interested in the output of echo ::memstat | mdb -k Am still in the early ...
1
vote
2answers
137 views

Optimize Linux file system for reading ~500M small files

We're seeing performance problems on a file system that contains ~500 M files that are relatively small (typically tens of kb) and ~150 K directories. Files access is predominantly reads and writes ...
0
votes
0answers
9 views

Does Intel's FlowDirector work for multicast traffic?

FlowDirector works by sampling outgoing packets, and establishing a core<->flow association so that when packets come in, it can lookup which core to send it by way of the usual RSS 3 or 5-tuple. ...
0
votes
1answer
43 views

Delaying packets with libnetfilter_queue

From my Raspberry Pi configured as an access point, I set the following rules: sudo iptables -I FORWARD -p tcp --sport 25 -j NFQUEUE --queue-num 0 sudo iptables -I FORWARD -p tcp --sport 80 -j ...
7
votes
1answer
249 views

Why is FileZilla so much faster than PSFTP?

I'm using FileZilla 3.10.3 and PSFTP 0.63 (PuTTY). Can anyone help me figure out why the throughput I get is so drastically different between the two clients? It can't just be a shortcoming of the ...
0
votes
0answers
62 views

Why a VPN slows down LAN access?

We have an access server providing VPN to some of our clients and the workforce with laptops. They usually connect from outside of the office, and everything works fine. However, for simplicity and ...
6
votes
1answer
193 views

4X10GB Bonded NIC - only producing 4-5GB throughput

I have Two HPBL685c G6 blade servers running Ubuntu 15.04 Each server has 4X10GB NIC 2x10GB NIC are connected to a single VirtualConnect 10/10G Ethernet module The other 2x10GB NIC are connected to ...
0
votes
1answer
24 views

Is “'Light-Speed' Disk Access” really a thing? [closed]

I just saw an advert for Hyve hosting on You Tube. One statement made me curious, they said they offer "'Light-Speed' Disk Access": Is this just a fancy way of saying they have optical technology, ...
0
votes
1answer
108 views

OpenZFS on OSX filesystem dataset performance issue

tl;dr - My ZFS RAIDZ2 array reads at 7.5+ GB/s and writes at 2.0+ GB/s when I specify a bs=128K or greater with dd. OS X is assuming 1K (as per stat -f %k .) and all my is ~300MB/s; dd gives the same ...
0
votes
0answers
24 views

Azure ASP.NET website http requests queued

We have a website deployed on Azure that has dreadful performance. When load increases, response times increase to whole minutes! CPU load is not even high, somewhere in the 40% region (we run one ...
0
votes
2answers
35 views

I/O and RAM limitations are important for Hadoop performance. But is disk speed related to I/O?

Hortonworks says this: "Most often performance of a Hadoop cluster will not be constrained by disk speed – I/O and RAM limitations will be more important." * How is disk speed not related to I/O ...