On Sun, Feb 10, 2013 at 5:15 AM, John Gordon <john.gor...@microsoft.com> wrote: Hi John,
> Env variables hang off of the session context and are specific to both the > user profile and their shell-specific preferences. If your driver is > loading in kernel mode, it cannot depend on env variables. > Our driver has relationships with Libvirt, HDFS and QEMU directly. And, IIUC, these are all loading in User Mode. I think GNULIB which called by Libvirt may change the Env variables. > This will be a problem for the other environment variables like hadoop_home. > > Instead of using Java directly in kernel mode, I suggest splitting the > problem: > 1. fs abstraction for the kernel > a. Like the nfs filesystem kernel driver implementation for example -- a > remote mount fs. > b. use a c impl of the protocol > I. To avoid issues, use hadoop 2.0 for protobuffs, since they yield a > versioned protocol to avoid hangs and dumps when the protocol changes. > II. OR push most of your implementation into a proxy service > a. Surface NFS directly, and just use the nfs kernel driver > b. Surface your own protocol to be consumed in the kernel mode > driver. > 2. Start hdfs elsewhere, as a independent service in user mode like cups, > httpd, or xinetd. > a. Will have a session and the ability to configure env vars. > > > Not sure if that exactly answers the question, but I hope it was helpful. > Absolutely helpful, we will take into account up ways you suggested. Thanks for your help very much ;-) -- Thanks Harry Wei
