Server: Intel® Core™ i7-3930K 6 core, 64 GB DDR3 RAM, 2 x 3 TB 6 Gb/s HDD SATA3
OS (uname -a): Linux *** 3.2.0-4-amd64 #1 SMP Debian 3.2.65-1+deb7u1 x86_64 GNU/Linux
Redis server 2.8.19
On the server to spin Redis-server, whose task is to serve requests from two PHP servers.
Problem: The server is unable to cope with peak loads and stops processing incoming requests or makes it very slowly.
Which attempts to optimize server I made:
cat /etc/rc.local
echo never > /sys/kernel/mm/transparent_hugepage/enabled
ulimit -SHn 100032
echo 1 > /proc/sys/net/ipv4/tcp_tw_reuse
cat /etc/sysctl.conf
vm.overcommit_memory=1
net.ipv4.tcp_max_syn_backlog=65536
net.core.somaxconn=32768
fs.file-max=200000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
cat /etc/redis/redis.conf
tcp-backlog 32768
maxclients 100000
What are the settings I found on redis.io, which is in blogs.
Tests
redis-benchmark -c 1000 -q -n 10 -t get,set
SET: 714.29 requests per second
GET: 714.29 requests per second
redis-benchmark -c 3000 -q -n 10 -t get,set
SET: 294.12 requests per second
GET: 285.71 requests per second
redis-benchmark -c 6000 -q -n 10 -t get,set
SET: 175.44 requests per second
GET: 192.31 requests per second
By increasing the number of customers is reduced query performance and the worst thing, Redis-server stops processing incoming requests and servers in PHP there are dozens of types of exceptions
Uncaught exception 'RedisException' with message 'Connection closed' in [no active file]:0\n
Stack trace:\n
#0 {main}\n thrown in [no active file] on line 0
What to do? What else to optimize? How do such a machine can pull customers?
Thank you!
Related
I have created 2 Standard HB120rs v2(RDMA capable) Virtual Machines on Azure with centos-based HPC,
On "ifconfig" I am getting below ips for 2 machines
I tried testing rping using the below commands
On instance 1 executed
rping -v -s -a 172.16.1.66 -C 10
On instance 2 executed
rping -v -c -a 172.16.1.66 -C 10
On doing this I am getting below error
cma event RDMA_CM_EVENT_ADDR_ERROR, error -110
waiting for addr/route resolution state 1
rping is not working. How to connect between two Mellanox devices from 2 VMs in azure.
I'm experiencing some problems with my internet connection so my provider told me to make a logfile for an evening (min. 3 Hours) to see when the connection drops out to see what's the cause of the problem.
When I'm losing connection, I still remain in the network but my Inernet is simply 0B/s. Is there a way to make a log for a certain Time interval that constantly checks the internet connection (and ideally the download/upload speed). I'm kinda beginner in the Linux world and it would be very helpful when the answer will be good explained and every step will be described.
Thanks in advance.
For checking every 10 seconds that your connection is available you could use
ping 8.8.8.8 -D -i 1 2>&1 | tee my.log
where 8.8.8.8 is a DNS server run by Google.
File my.log will receive entries like:
[1583495940.797787] 64 bytes from 8.8.8.8: icmp_seq=1 ttl=55 time=17.9 ms
[1583495950.809658] 64 bytes from 8.8.8.8: icmp_seq=2 ttl=55 time=18.7 ms
ping: sendmsg: Network is unreachable
The number in square brackets is the time in seconds since 1970-01-01T00:00:00Z. For our example:
1583495950 = 2020-03-06T11:59:10Z
If you want to really transfer data, you could use a script like:
#!/bin/sh
URL=https://example.com
while [ true ]
do
wget $URL -O /dev/null 2>&1 | grep 'saved' | tee my.log
sleep 10
done
But mind the traffic cost on both sides.
I'm trying to get memory metric from client machine. I installed nrpe in client machine and works well for default checks like load, users and all.
Manual output from client machine,
root#Nginx:~# /usr/lib/nagios/plugins/check_mem -w 50 -c 40
OK - 7199 MB (96%) Free Memory
But when i try from server, other metrics works but memory metrics not working,
[ec2-user#ip-10-0-2-179 ~]$ /usr/lib64/nagios/plugins/check_nrpe -H 107.XX.XX.XX -c check_mem
NRPE: Unable to read output
Other metrics works well
[ec2-user#ip-10-0-2-179 ~]$ /usr/lib64/nagios/plugins/check_nrpe -H 107.XX.XX.XX -c check_load
OK - load average: 0.00, 0.01, 0.05|load1=0.000;15.000;30.000;0; load5=0.010;10.000;25.000;0; load15=0.050;5.000;20.000;0;
I ensured that check_mem command has execution permission for all,
root#Nginx:~# ll /usr/lib/nagios/plugins/check_mem
-rwxr-xr-x 1 root root 2394 Sep 6 00:00 /usr/lib/nagios/plugins/check_mem*
Also here is my client side nrpe config commands
command[check_users]=/usr/lib/nagios/plugins/check_users -w 5 -c 10
command[check_load]=/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 30,25,20
command[check_disk]=/usr/lib/nagios/plugins/check_disk -w 20% -c 10% -p /dev/sda1
command[check_zombie_procs]=/usr/lib/nagios/plugins/check_procs -w 5 -c 10 -s Z
command[check_procs]=/usr/lib/nagios/plugins/check_procs -w 200 -c 250
command[check_http]=/usr/lib/nagios/plugins/check_http -I 127.0.0.1
command[check_swap]=/usr/lib/nagios/plugins/check_swap -w 30 -c 20
command[check_mem]=/usr/lib/nagios/plugins/check_mem -w 30 -c 20
Can anyone help me to fix the issue?
what is the maximum number of websockets any one has opened using jetty websocket server. I recently tried to load test the same and was able to open 200k concurrent connections on a 8 core linux VM as server and 16 clients with 4 core each. Each client was able to make 12500 concurrent connections post which they started to get socket timeout exceptions. Also I had tweaked the number of open files as well as tcp connections settings of both client and server as follows.
sudo sysctl -w net.core.rmem_max=16777216
sudo sysctl -w net.core.wmem_max=16777216
sudo sysctl -w net.ipv4.tcp_rmem="4096 87380 16777216"
sudo sysctl -w net.ipv4.tcp_wmem="4096 16384 16777216"
sudo sysctl -w net.core.somaxconn=8192
sudo sysctl -w net.core.netdev_max_backlog=16384
sudo sysctl -w net.ipv4.tcp_max_syn_backlog=8192
sudo sysctl -w net.ipv4.tcp_syncookies=1
sudo sysctl -w net.ipv4.ip_local_port_range="1024 65535"
sudo sysctl -w net.ipv4.tcp_tw_recycle=1
sudo sysctl -w net.ipv4.tcp_congestion_control=cubic
On the contrary one 2 core machine running node was able to scale upto 90k connections.
My questions are as follows
Can we increase the throughput of jetty VM any more
What is the reason of node.js higher performance over jetty.
Facing a peculiar problem when doing load testing on my laptop with 2000 comcurrent users using cometd. Following all steps in http://cometd.org/documentation/2.x/howtos/loadtesting.
These tests run fine for about 1000 concurrent client.
But when I increase the load to about 2000 CCUs, the terminal just shuts down.
Any idea what's happening here?
BTW, i have followed all the OS level settings as per the site. i.e.
# ulimit -n 65536
# ifconfig eth0 txqueuelen 8192 # replace eth0 with the ethernet interface you are using
# /sbin/sysctl -w net.core.somaxconn=4096
# /sbin/sysctl -w net.core.netdev_max_backlog=16384
# /sbin/sysctl -w net.core.rmem_max=16777216
# /sbin/sysctl -w net.core.wmem_max=16777216
# /sbin/sysctl -w net.ipv4.tcp_max_syn_backlog=8192
# /sbin/sysctl -w net.ipv4.tcp_syncookies=1
Also, I have noticed this happened even when I run load tests for other platforms. I know this has to be something related to the OS, but I cannot figure out what it could be.
ulimit command has been executed correctly? I read something about it in Ubuntu forum archive and Ubuntu apache problem.