I have a secondary storage drive thats partition like below.
Number Start End Size Type File system Flags
1 1049kB 56.4GB 56.4GB primary ext4
2 56.4GB 500GB 444GB extended
5 56.4GB 61.7GB 5369MB logical ext4
6 61.7GB 500GB 438GB logical ext4
How do I safely shrink partition number 6 and reallocate the free space to partition number 1 without using a cd?
I have a xen HVM vps and I'm trying to raise the hard and soft file limits for nobody at boot time. I'm using Ubuntu 10.04.3 and inside /etc/security/limits.conf I have:
nobody soft nofile 10000
nobody hard nofile 30000
But when I check the file limits are still the default 1024:
su nobody -c 'ulimit -Hn'
1024
su nobody -c 'ulimit -Sn'
1024
What is the right way of raising the file limits for Ubuntu?
I'm trying to transfer about 100k files totaling 90gb. Right now I'm using rsync daemon but its slow 3.4mb/s and I need to do this a number of times. I'm wondering what options do I have that would max out a 100mbit connection over the internet and be very reliable.
I'm wondering if its safe to use multiple rsync instances with the same command line to backup the same directory on the local server to the same directory on the remote server? basically if I ran the command below 3-4 times in parallel would it help speed things up? The recieving server is using rsyncd.
rsync -av /home/directory/ [email protected]::Home
I have a xen hvm vps with a console thats accessible using VNC. I'm wondering if there's any way of logging anything/everything that is sent to console? I'm trying to log the console cause my vps crashes everyday for some odd reason.
I'm wondering if you need to reboot if you make changes to settings related to linux tcp such as tcp_window_scaling.
I'm trying to improve the throughput of one of my servers overseas and after monitoring a transfer between the server and my home computer with wireshark I'm pretty sure I have a problem with the window size.
For an ftp transfer I get a receive window size of 14720.
Window size value: 115
Calculated window size: 14720
Window size scaling factor: 128
My send window looks like what I set it to:
Window size value: 65335
Calculated window size: 261340
Window size scaling factor: 4
So how do I fix the rwindow? I've gone through the linux tcp settings on my server and everything seems normal. Timestamps are on, syncookies are off, scaling is on, sacks are on, cubic is the congestion control method, max receive and send window size is 3mb. I've tried changing the default tcp_wmem and tcp_rmem values but it does nothing.
EDIT:
When I turn off autotuning and/or window scaling on the server the window shrinks to 14600, which is basically 10x the MSS.
5337 4.268584 2.2.2.2 1.1.1.1 FTP 106 Response: 227 Entering Passive Mode (2,2,2,2,240,15).
5338 4.268640 1.1.1.1 2.2.2.2 TCP 74 59855 > 61455 [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=431721460 TSecr=0 WS=128
5364 4.300368 1.1.1.1 2.2.2.2 TCP 54 57609 > ftp [ACK] Seq=217 Ack=648 Win=15744 Len=0
5480 4.346856 2.2.2.2 1.1.1.1 TCP 66 61455 > 59855 [SYN, ACK] Seq=0 Ack=1 Win=5840 Len=0 MSS=1460 SACK_PERM=1 WS=128
5481 4.346867 1.1.1.1 2.2.2.2 TCP 54 59855 > 61455 [ACK] Seq=1 Ack=1 Win=14720 Len=0
5482 4.346893 1.1.1.1 2.2.2.2 FTP 70 Request: STOR 100mb.bin
5570 4.428061 2.2.2.2 1.1.1.1 FTP 109 Response: 150 Opening BINARY mode data connection for 100mb.bin
5571 4.428078 1.1.1.1 2.2.2.2 TCP 54 57609 > ftp [ACK] Seq=233 Ack=703 Win=15744 Len=0
5572 4.428155 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
5573 4.428166 1.1.1.1 2.2.2.2 FTP-DATA 1514 FTP Data: 1460 bytes
5662 4.505384 2.2.2.2 1.1.1.1 TCP 60 61455 > 59855 [ACK] Seq=1 Ack=1461 Win=8832 Len=0
5663 4.505392 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
5664 4.505421 2.2.2.2 1.1.1.1 TCP 60 61455 > 59855 [ACK] Seq=1 Ack=2921 Win=11776 Len=0
5665 4.505429 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
5666 4.505535 2.2.2.2 1.1.1.1 TCP 60 61455 > 59855 [ACK] Seq=1 Ack=4381 Win=14720 Len=0
5667 4.505543 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
5734 4.583769 2.2.2.2 1.1.1.1 TCP 60 61455 > 59855 [ACK] Seq=1 Ack=5841 Win=17536 Len=0
5735 4.583778 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
5736 4.583781 2.2.2.2 1.1.1.1 TCP 60 61455 > 59855 [ACK] Seq=1 Ack=7301 Win=20480 Len=0
5737 4.583787 1.1.1.1 2.2.2.2 FTP-DATA 2974 FTP Data: 2920 bytes
I transfer large files between two of my servers one in the US and the other in the Netherlands and I'm wondering if there are any tweaks I can apply that will increase the speed of a transatlantic tcp transfer (ftp or http).
Right now I'm running on the defaults of Ubuntu natty except for rmem_max and wmem_max which I increased according to a BDP calculator.
I have a root filesystem thats live and mounted and I'd like to convert it to ext4. All the howto's i've read deal with booting off a live CD but thats not an option.
I have a couple of blogs running on an Ubuntu 9.04 machine and I'd like to upgrade it. Is it safe to do so?
Note, I also have a few daemons that were manually compiled like MySQL, Nginx, PHP, etc.
Is there a benchmark program I can use to measure random read speeds of a vps without interference from the kernel cache? Also looking for something where you can change the read sizes say 4k-64k.