Digital Wasabi

Alright. I've finally got around to doing some Snappy testing. I've gotten some amazing results, but also noticed a bug. My current code seems to hang after a large amount of compression. It specifically hangs when i am doing an iozone benchmark. The 500MB pass (I set it to 4GB). But before I ran iozone, i did some paliminary testing vs lzjb, and I have to say, the compression performance is higher with Snappy. I was able to get a 23.14  compression ration instead of the 15.22 ratio from lzjb, with similar cpu usage. I suspect this has to do with the snappy_env_init method in the snappy-c library i found. It seems fishy having to initializing the environment for every compression event. I may look into it further but it does not seem very scaleable. and given that ZFS compression works at the block level, and not the file level, there are a lot of compression events happening for a single file (instead of one event, compressing a 400MB file...it would be 400 events with...

I've completed my first zfs + snappy build. Its up on github at  https://github.com/techsaint/zfs-snappy . I tried to test it on my Virtualbox instance, but it doesn't look like there is very good VDI support for zfs. It seems to freeze when i try to write to a file system. I tried with the non snappy version too, just in case I mucked up something, but the vanilla version also froze. Now that I have a compatible version, I will test it on actual hardware, instead of in a VM. This build actually has snappy baked into zfsonlinux using the snappy-c library I found. If this route works, I will look at using the snappy-c port in an illumos build. I have all the changes out on bitbucket, and I did spend a few months learning the opensolaris/illumos build files....

My ZFS/Snappy project was put on hold, because of technical issues and lack of understanding (and documentation) of how to integrate a library into an Illumos build. I may have found a compromise. The zfs on linux project has become a bit more mature. I may switch up and use linux to create a snappy proof of concept.   I understand linux build structure much more than open solaris build structure, and the things i dont understand are fairly well documented. Because zfsonlinux is on github , I'll most likely be using Github and forking the project.