em, okay after Bob posted something really not helpful, I will chime in too.
It is not the automount demon. It is linux destroying interactivity and starving readers when their is disk based (and in this case, a dvd is a disk) IO. Old problem, you can go to lkml and complain a bit... but countless others have done the same. Two things: increase readahead. A lot. Not that stupid package, the kernel setting. And if you are using SDDs use the no-op IO-scheduler. 2013/7/25 Bob Sanders <rsand...@sgi.com> > Mark Knecht, mused, then expounded: > > Hi all, > > I'm wondering what folks who understand Linux configuration better > > than I do about a problem like this. I run media all day while working > > on my Gentoo/KDE box. The machine is generally over powered for 99% of > > the work I do. It works _very_ hard when I kick off big numeric runs > > (i.e. 100% usage for 2-30 minutes) but most of the time CPU usage is > > running at <1-2% while I'm doing things like editing code and watching > > a movie at the same time/ > > > > What I do notice however is that whether I'm watching NetFlix in a > > VM or a movie on disk using VLC, when I insert a DVD I almost always > > get a glitch of 1-2 seconds while the system figures out what to do > > with the DVD. I see some CPU usage, but it's not like 12 processors go > > to 100%. > > > > As no one has stepped in here...Pretty much everything I;m suggesting, > you are going to hate. > > - Turn off that system sucking automount daemon. > > Hopefully, that fixes the issue for you. The rest are more drastic. > > Here are the important things for a VM host, in order of decreasing > importance - > > 1) Storage - needs twice as much, must be fast. 7200 RPM SATA drives > are acceptable for read only NFS stores. > > 2) Memory - all DIMM slots filled, 8GB 1600 PC3-DDR DIMMS minimum. > Faster, lower latency, DIMMs preferred, but motherboard/bios may > down clock them. > > 3) Network - Wide bandwidth (Probably not an issue for you). 10GigE > minimum. Or bond at least 4 GigE ports to act as a single pipe. > > 4) CPU - Lower core count, 8-cores/socket max. More eats up I/O > Bandwidth, adds latency, generates wait states. Better to > oversubscribe the cpu than anything else. > > On an even more micro level - > > Storage - Make sure you have seperate drives for the OS - mostly read > only), /var - mostly write, and /home - mostly read, light write. > Typical setup would be a single SSD for the OS, RAID 1 for /var and > whatever RAID you like for /home using 10K RPM SAS drives preferred. > > Use the proper file system - large sequential files: media, VM > images, etc. need XFS. Small r/w files need - EXT3. > > Use a proper hardware RAID card - not a software raid. Proper > hardware raid cards will require a x8 PCIe slot and cost a few > hundred dollars. > > Reduce the cpu core count to 4 and offload your numeric compute > requirements to a stack of RasberryPI compute engines, using your > main system as a head node for the cluster. > > Bob > -- > - > > >
