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Jan
5
comment Where did my RAM go?
@Benjamin I don't know any way to see what's in the dentry cache. But running strace may be instructive. Do you use libcurl? What's your app doing?
Jan
5
comment Where did my RAM go?
@Benjamin Follow my link for one example of how this can happen. Also, look at what the web application is actually doing.
Jan
5
answered Where did my RAM go?
Jan
2
answered What happen if a systemd service reach its MemoryLimit?
Jan
2
comment Clearing Memory (RAM) Cache on CentOS
Are you seriously asking how to get your computer to waste more memory rather than using it efficiently?
Jan
2
comment How many bits of entropy per byte read from /dev/random and /dev/urandom?
@DanielKauffman I have no idea what that means.
Jan
2
comment How many bits of entropy per byte read from /dev/random and /dev/urandom?
@DanielKauffman You can already read however many bytes you want/need from /dev/urandom directly. Hashing is really only helpful if you want to combine entropy from multiple sources.
Dec
31
answered How many bits of entropy per byte read from /dev/random and /dev/urandom?
Dec
30
comment Data Transfer Speed Hardware Config
@Alan When it maxed out, what maxed out? CPU? Memory? I/O?
Dec
30
comment multiple internet connection at office
@Krunal Support for enterpricey features like tunnels.
Dec
24
comment Iptables block connection from specific IP - to another IP
@Beginner Something is very wrong with your understanding of something because the comment above is incoherent. What does it mean for a host name to use an IP address as a DNS server? And what traffic are you trying to block? Traffic to a DNS server?
Dec
16
comment HP Procurve 2920 VLANs with DHCP cannot ping
That doesn't make sense. If the server already has an IP address inside 192.168.x.0, it shouldn't need a route. And if it doesn't have an IP address inside 192.168.x.0, it shouldn't know how to reach 192.168.x.2 without a route that would also work for the rest of 192.168.x.0/24.
Dec
11
comment Swap 99% but regular memory fine
What is swappiness set to?
Dec
11
comment Swap 99% but regular memory fine
Right. It seems like his system is making a rational tradeoff. It doesn't have an awful lot of RAM, so it's moving rarely used stuff to swap to make more physical RAM available. The tradeoff is that when rarely used stuff is actually used, there's a performance hit. The benefit is that the most used stuff is faster.
Dec
8
comment Connect two mikrotik LAN
Don't bridge two IP networks through a pseudobridge. Pseudobriding is only suitable for bridging a single layer 2 device.
Dec
6
answered Need to understand : ping
Dec
1
comment HP Procurve 2920 VLANs with DHCP cannot ping
To be clear, you are saying 192.168.1.1 cannot ping 192.168.0.1, even though both have the switch as their default gateway? Is that correct?
Dec
1
comment HP Procurve 2920 VLANs with DHCP cannot ping
Can the machines ping the switch's other addresses? Can 192.168.1.1 ping 192.168.0.2? Can 192.168.0.1 ping 192.168.1.2?
Nov
27
comment Software RAID 10 not any faster than s/w RAID 5 on Ubuntu 14.04 box, why?
@chutz Why do you think that makes any difference?
Nov
27
comment Software RAID 10 not any faster than s/w RAID 5 on Ubuntu 14.04 box, why?
@chutz He's not testing small random writes. But in any event, the same thing applies to RAID 10. If you change just one byte, it has to read the entire block containing that byte.