Lazy Reading for 2013/09/08

By the time you read this, I’ll have already been sitting on an island for a few days.  There’s so much stuff to post lately I’m scheduling material a week out.

Your unrelated comic link of the week: The Scout, by Malachi Ward.  A self-contained sci-fi story.

In Other BSDs for 2013/09/07

There’s been a lot of commit activity across the BSDs, but my list doesn’t seem to reflect that.  A lot of incremental work, I suppose.

TCP improvements

Sepherosa Ziehau has made a number of improvements to TCP in DragonFly – specifically, nonblocking and blocking connect(2) performance.  See each of his commits for statistics on how much this has reduced processor use under high load.  He has also written up an extensive description of how all this TCP stuff works in DragonFly.

In similar news, he has a nginx patch that delivers a significant performance increase.  It may go into nginx itself.

DragonFly and Summer of Code, week 11

Almost done with this year’s GSoC.  It’s been astonishingly… easy?  The students are working and the problems are difficult, but there’s been very little in the way of crisis.

Lazy Reading for 2013/09/01

Another week of links completed early.  And there’s a lot, so get clicking!

Your unrelated link of the week: The remix of this 1997 Kid’s Guide to the Internet – somewhat NSFW, and has all the best moments.  More from EVERYTHING IS TERRIBLE.

In Other BSDs: 2013/08/31

I need to update this post during the week as I see stuff, or else I spend an hour rushing to get it all together before Satuday.  I need to start watching PC-BSD src changes, too.

Deduplication benefits, again

Remember my recent disk issues?  As a side effect of protecting myself, I have a good example of deduplication results.

I have a second disk in my server, with slave Hammer PFSs to match what’s on my main disk.  I hadn’t put them in fstab, so they weren’t getting mounted and updated.  I got them re-created, but they were nearly full.  Here’s an abbreviated df, from which you should be able to tell which drives I have :

Size   Used   Avail   Capacity
929G   729G   200G    78%    /slave/slavehome
929G   729G   200G    78%    /slave/slavevar
929G   729G   200G    78%    /slave/slaveusr
929G   729G   200G    78%    /slave/slaveslash

That 78% is how full the Hammer volume was.  I turned on Hammer deduplication, since it’s off by default.  The very next day:

Size   Used   Avail   Capacity
929G   612G   318G    66%    /slave/slavehome 
929G   612G   318G    66%    /slave/slavevar 
929G   612G   318G    66%    /slave/slaveusr 
929G   612G   318G    66%    /slave/slaveslash

It’s a 1 terabyte disk, and I gained more than 10% back – That’s 100g of disk space that I gained overnight.  There might be more tomorrow, given that it was all of 5 minutes of dedup work.

This won’t surprise you if you’ve seen previous deduplication links here, like my previous results or some real-world tests.  It’s still great.  I’d suggest turning it on if you haven’t – hammer viconfig the appropriate PFS and uncomment the dedup line.

 

DragonFly and Summer of Code, week 10

Only 3 more Mondays left in the student work part of Summer of Code!  Unsurprisingly, it seems the students are mostly in the cleanup phase – as it should be.