All Questions
Tagged with performance performance-tuning
117
questions
0
votes
0
answers
76
views
Performance for static files (HTML, CSS and JS) of PHP Server - CDN vs NGINX
Without going too much into detail to avoid that this question becomes opinion-based; so talking from a purely technical perspective: When you currently have a PHP-Apache setup, both PHP and Apache ...
- 187
12
votes
2
answers
5k
views
How dangerous might it be - and what performance gains may be had - by turning vulnerability mitigations off on non-Internet facing servers?
When a virtual machine Linux host server is non-Internet facing and is used exclusively on a LAN and is using a relatively well tested distribution like Proxmox, how dangerous would it be to turn off ...
- 1,185
0
votes
0
answers
156
views
Are there any big performance boost when upgrade from Ubuntu 16.04 to 22.04?
If I run the server as MySQL database. (Assume using the same MySQL version).
Are there any big performance boost when upgrade from Ubuntu 16.04 to 22.04?
- 5,871
0
votes
1
answer
130
views
Is it necessary to ban malicious IP regardless of default firewall setting being deny/reject?
I'm on Linux and using fail2ban as the ban system. So far, it has collected and banned about 150K of malicious IPs, and I'm concerned and wondering if this will gobble a fair amount of resources. As I ...
- 1
1
vote
1
answer
1k
views
Samba and luks encrypted disk together: Huge performance loss despite plenty of CPU resources, LUKS and samba alone works as expected
Setup:
SSD encrypted with luks aes-xts 512 bits (256 bits AES key), ext4 filesystem
dd write performance of 138 MB/s, CPU usage 97-100 %
dd if=/dev/zero of=testfile status=progress bs=32M count=128
...
- 307
0
votes
1
answer
4k
views
How to do performance tuning of Apache server?
We have an apache server 2.4.X which we are using as a reverse proxy in front of one Java Application . We have enabled Apache status module Apache Status and we are able to see that number of idle ...
- 103
2
votes
0
answers
133
views
Index rollover latency
I have created an ILM policy as follows,
{
"policy": {
"phases": {
"hot": {
"min_age": "0ms",
"actions": {
"rollover": {
"max_docs": 30
},
...
- 141
1
vote
1
answer
639
views
Bottleneck identification using iostat, vmstat, mpstat
I am doing some Apache and MySQL performance tests, then upgrading a single component and running tests again to see where the bottlenecks are. I have a local used server warehouse (Tams in Lindon UT) ...
- 543
2
votes
2
answers
1k
views
DoS attack? Vast majority of apache workers in 'Reading Request' mode, site down last night, slow now
So I think my server might be suffering a Denial of Service attack.
We got notified by pingdom (website monitoring) that our website was unavailable starting around 3AM. Early today we started ...
- 536
1
vote
2
answers
2k
views
Serving a static website with nginx. Response time over 600 milliseconds. What’s wrong?
I serve a wordpress blog with nginx http cached to over 99% of the requests with a cache lifetime of 2 days. Here’s a webpage from the site. The webpages have quite a few images and therefore lazy ...
- 791
2
votes
2
answers
289
views
How to ask antivirus software to work slower and hence use less disk access?
It is our policy for our end-user's computers (usually laptops) to have high power CPUs, GPUs, RAMs (no less than 16GB) and HDD space (1TB), but we save money by choosing lower rotation speed of HDD. ...
- 111
1
vote
2
answers
100
views
Is it possible for Windows clients to carry out external queries through an alternative DNS server directly?
Our Windows domain is far away. DNS performance is affected. Would it be possible for Windows clients to carry out external queries through an alternative DNS server directly? I understand this is not ...
- 458
6
votes
2
answers
4k
views
Nginx: Optimizing server response time for a HTTP cached website
I have a website with all of the pages served from nginx’s http cache and rarely invalidated or expired.
The average total page download size is around 2 MB
But despite being a static site with no ...
- 4,413
8
votes
2
answers
882
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 ...
- 616
1
vote
0
answers
140
views
Performance on Pinned CPU cores versus automatically managed?
I have a XenServer 7.5 environment where I'm running a single Windows VM with 16 total vCPU's. My server has dual Xeon E5-2620v4 CPU's with 8cores/16threads each clocked at 2.1GHz nominal and a Max ...
- 403
0
votes
1
answer
2k
views
Slow apache response time for json api (solved)
I've got an Apache server hosting several json APIs.
This server is running Ubuntu 16.04.4 LTS with Apache and Mysql.
Response times for all API are very good except for one! It takes about 5s to ...
- 1
5
votes
1
answer
790
views
Misunderstanding about Page Cache and dirty_background_bytes
I've been looking at this for a while now and things aren't lining up with my expectations, but I don't know if it's because something is off, or if my expectations are wrong.
So, I've got a system ...
- 161
6
votes
2
answers
12k
views
Hyper-V Windows Server 2016 VM is super slow
I have a Hyper-V VM, both host and VM are running Windows Server 2016. The VM has Exchange 2016 installed and takes an hour to start up fully (all Exchange services). It is actually very solid when up ...
- 263
2
votes
2
answers
978
views
Two identical systems with very different performance
I have two Dell R730 systems which have an identical hardware configuration purchased at the same time. Both are running RHEL6.9 where were imaged from the same image. It was imaged in January. I ...
- 167
1
vote
1
answer
350
views
Diagnosing slow/timing-out web application
I'm seeing average load times of load average: 12.41, 11.94, 11.59 on a linux-based machine serving a web application. It has 16 cores, so the load average isn't unmanageably high.
However, this web ...
- 2,365
0
votes
0
answers
146
views
Cannot get performance improvement with Haproxy
I have 4 web servers with a ruby web server running, and a server running haproxy.
I can get a RPS(request per second) of 300 against one web server using ab.
But I can only get a RPS of 340 against ...
- 449
0
votes
1
answer
335
views
Backuppc performance dropped dramatically
I've got a tiny server in my house which I use for file server and hosting test web sites for my clients, among other things. It uses backuppc for backups. The machine is a MSI Cubi N, backing up to a ...
- 553
0
votes
1
answer
94
views
What constant throughput and linear respone time tells about the system?
What does it mean when throughput in the system is constant and only response time changes (linearly)?
Does it mean that I have to have a bottleneck?
- 111
2
votes
1
answer
1k
views
Slow SSD performance - IBM X3650 M4 (7915)
I set up a test environment for development purposes. It consists of a IBM X3650 M4 (7915) server with:
2 x Intel Xeon E2690 @ 2.90GHz
96GB 1333MHz ECC RAM
2 x HDD 146GB 15k rpm
6 x SSD 525GB (...
- 179
2
votes
1
answer
10k
views
How increase write speed of raid1 mdadm?
CentOS, Xeon 1230, 16 Gb RAM, 2x1TB SSD in raid1 (mdadm).
Read from raid1 vary from 130 to 250 MB/s depends of files etc.
But write speed very slow: 15-20 MB/s (iotop, mc etc.)! You know the real ...
- 71
1
vote
2
answers
194
views
What performance statistics can I use to determine if hyperthreading will improve performance?
There are several questions asking if disabling hyperthreading will improve performance (e.g. like this). The answer (as it is to all performance questions) is of course "profile it on your workload"....
- 111
0
votes
1
answer
124
views
Two identical servers. One with extremely poor performance
I have these two servers with the following specs:
OS: RHEL 6.3 Hardware: Dell PowerEdge R610, 12 cores, 64GB RAM Drives: 6 x Samsung 840 Pro SSD RAID controller: Intel RS25AB080, 1GB Cache RAID ...
0
votes
1
answer
666
views
Why is Haproxy hitting (variable) connection limits?
I'm trying to understand some numbers I'm seeing as well as why Haproxy seems to be hitting variable limits on requests/s.
The test set up is pretty straightforward:
20 backend servers running on ...
- 101
3
votes
2
answers
3k
views
Stand alone single thread optimized server vs vm running on VMWare
I apologize for the length of my post.
We recently converted our business system to a product that is licensed by the number of Cores.
We purchased the 2 core license and are currently running it on ...
- 31
1
vote
1
answer
2k
views
Zabbix : How to acheive 1s interval with active items?
Is it even possible/recommended ?
We are trying to set up few active items configured with a 1 second interval. However those items don't keep up the desired interval, instead we are gathering a ...
- 11
-3
votes
1
answer
79
views
Analyzing server performance [duplicate]
We have recently finished work on one ecommerce site which is built on opencart 2.x and site has around 1k products. The site is currently running on VPS server.
For some days we are facing some ...
- 1
0
votes
0
answers
214
views
Mongodb, we can't go over 100 insert/sec on 200iops HDD
Thanks in advance for your help, we get a strange behaviour in mongodb. So we have a cluster of 20 shards, each composed of 1 master and 2 slaves. This database has a heavy load of write only. However ...
- 101
1
vote
1
answer
492
views
Persist statistics data from Postgres' stats_temp_directory on demand
We are investigating I/O load in one of our VMs and possibilities to optimize it and it showed that most of the load is generated by the stats collector of PostgreSQL. It jumps between 3,5 and 6,5 MB/...
13
votes
1
answer
2k
views
Virtualization - Ten 1Gbps links or one 10Gbps link? (Performance)
I have a machine that has several VM's (5) and 3 physical networking cards (with each 2 ports), with a total of six 1Gbps ethernet ports.
I have a SPF-capable switch, having a total of 48Gbps ...
- 289
34
votes
2
answers
4k
views
Why is my bare-metal 16x 2.93GHz cores computer performing poorer than a VPS with 4x 2.5GHz cores?
I have a written a piece of multi-threaded software that does a bunch of simulations a day. This is a very CPU-intensive task, and I have been running this program on cloud services, usually on ...
0
votes
0
answers
655
views
Google Cloud Long TTFB
Google Cloud seems to be having much longer TTFB than they specify in their documentation for cloud storage. You can see from this WPT result that it varies from 500 to 700 MS.
The documentation here ...
2
votes
4
answers
17k
views
Slow write Performance with HP H240 HBA using internal Storage with Raid 5 SSD's
I am having a HP Proliant DL 160 Gen9 Server with a HP H240 Host Bus Adapter.
6x 1 TB Samsung SSD's configured in a raid 5 directly using the internal storage of the machine.
After installing a VM on ...
- 1,451
-2
votes
1
answer
44
views
Find a load on my Web Server [duplicate]
As requested, I am asking the question here.
Is there a way to find a load on my web application server without a load / stress testing?
I have deployed my application in the Apache Tomcat server. ...
6
votes
1
answer
4k
views
Nginx performance when running multiple instances on the same machine
I'm trying to understand the performance impact of having multiple nginx instances (masters) running on the same machine, rather than having them all load into a single instance using different server ...
- 167
1
vote
0
answers
82
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 ...
- 111
3
votes
2
answers
3k
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
pm....
- 153
8
votes
1
answer
2k
views
What do users see when Apache reaches MaxClients?
Occasionally, in my Apache error log, I will find:
[error] server reached MaxClients setting, consider raising the MaxClients setting
I've purposely lowered MaxClients in the past (to 60) due to ...
- 287
1
vote
1
answer
164
views
Does Apache mod_status give any insight to tuning Apache config?
Does the Apache mod_status output give any insight to tuning Apache prefork config?
For example, using Apache's mod_status, I figured out that
My server gets 3 requests/sec average, the range is 2-...
- 287
2
votes
0
answers
1k
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:\ ...
- 121
3
votes
1
answer
2k
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 ...
- 1,386
0
votes
1
answer
935
views
Negative effects of setting nginx workers too high
I've seen numerous posts advising how to set nginx's worker_processes, but very few detailing what happens when this is set too high. I'm about to run some benchmarks, but I'd appreciate advice on ...
- 367
0
votes
0
answers
1k
views
Tunning nginx/php5-fpm : why low memory usage with 800 users?
I did optimize nginx with what I found on the internet
My specs are 2 servers load balanced :
Intel Xeon E5-1620v2 (4c/8t 3,7 GHz+/3,9 GHz+)
32 Go DDR3 ECC 1600MHz
3x 160Go SSD Intel DC S3500 SATA3 ...
- 498
2
votes
1
answer
151
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 ...
- 8,921
3
votes
4
answers
19k
views
NFS Over OpenVPN: Top Performance Boosters
I have two VPS's - One is running 2008 Server R2 and the other is a Ubuntu 12.04 installation. I am using the Windows VPS for RD sessions for Quickbooks and a couple other apps and using the Ubuntu ...
- 283
1
vote
0
answers
125
views
IRQ not handled by all CPUs
I have a problem about balancing irq. I took irq numbers from /etc/interrupts and assigned each irq to each of 24 CPUs as this tutorial says
for i in {143..166};do cat /proc/irq/${i}/smp_affinity; ...
- 431