I have tried everything that i can find on this site as well as the internet to turn off power management for the wireless card.
My current conf
user1@user1-Q500A:~$ iwconfig eth0 no wireless extensions. wlan0 IEEE 802.11bgn ESSID:"AJ_Home" Mode:Managed Frequency:2.412 GHz Access Point: 00:26:F2:FD:92:F4 Bit Rate=65 Mb/s Tx-Power=16 dBm Retry short limit:7 RTS thr:off Fragment thr:off Power Management:on Link Quality=55/70 Signal level=-55 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:53 Missed beacon:0 lo no wireless extensions.
These are the steps ive used in the past to disable the "wifi" power management during the installation of Ubuntu and it has always worked.
iwconfig to check power management ON for wlan0
sudo touch /etc/pm/power.d/wireless
sudo chmod 755 /etc/pm/power.d/wirelessOR
sudo chmod +x /etc/pm/power.d/wireless
sudo gedit /etc/pm/power.d/wireless
Copy/paste the following text into the empty text file "wireless":
#!/bin/sh /sbin/iwconfig wlan0 power off
Close and Save the text file.
iwconfigat term to verify wireless power management is off.
Unless something has changed with 15.04 i'm thinking this may be a bug.
I have tried this on 3 newly installed Xubuntu 15.04 computers and its the same on all.