anon (anon@anon.com) on 1/22/11 wrote:
---------------------------
>Rob Thorpe (rthorpe@robertthorpeconsulting.com) on 1/22/11 wrote:
>---------------------------
>>Linus Torvalds (torvalds@linux-foundation.org) on 1/20/11 wrote:
>>---------------------------
>>>Megol (golem960@gmail.com) on 1/20/11 wrote:
>>>>
>>>>Linus "ass***e" Torvalds not understanding something and insulting everyone that
>>>>have a clue. How come I'm not surprised?
>>>
>>>Why do you think I'm here? If I wanted to have an intelligent
>>>discussion with people I care about, I'd be writing emails
>>>to kernel people. "Arguing vigorously" is my hobby.
>>
>>To put things differently, for the purposes of RWT forums you're a troll.
>>
>>What I can't understand is why Dean and David have let your behaviour in this thread
>>go and not thrown it into the unmoderated forum.
>>
>>FWIW I don't know or care much about TRIM. But, I'm reminded of a line from "The Big Lebowski"...
>>
>>"You're not wrong Walter. You're just an asshole."
>
>Pretty sure everybody else was wrong and an asshole. Linus had actual numbers and
>real reasons. Everyone continued to bait him and handwave and assert how they were
>right and he was wrong with nothing to actaully back it up.

As a number of people pointed out, the numbers were intriguing and surprising...but it's hard to judge them given the lack of test conditions.

>Let's be clear here. People were not saying "Oh well I would have thought trim
>should be fast because X, so given the actual numbers and experiences you have provided, I wonder if Y".
>
>People were saying "No I'm right and you're wrong, trim is fast and obviously always
>right to always do it. I have no numbers and nothing but vague handwaving about
>what I believe an FTL should do, but in any case you are definitely wrong.".

Actually, it seems to me that the overall response was: "Yes, it appears that some drives with TRIM have a really really crappy implementation that causes problems, that doesn't necessarily mean that the idea sucks though."

TRIM is a pretty complex subject - it doesn't work real well in RAID and many enterprise systems will probably disable it, in favor of techniques that scale over multiple SSDs.

As was also pointed out, it many respects, a DRAM or SRAM write combining buffer is a vastly better solution - however many vendors avoid that for cost reasons. Some for data safety reasons. It seems to me that this is an area likely to see improvement...but hard to say.

The point that using TRIM as a crutch for a cheap/crappy SSD seems pretty valid. I think a more interesting point is whether a good TRIM implementation can improve performance/longevity for a properly designed and suitably robust SSD.

Another related question is whether changes in the FS would help (or not).

David