Re: [gentoo-user] Re: {OT} Allow work from home?

[lee]

Kai Krakow <hurikhan77@×××××.com> writes:

> Am Wed, 20 Jan 2016 01:46:29 +0100
> schrieb lee <lee@××××××××.de>:
>
>> The time before, it wasn't
>> a VM but a very slow machine, and that also took a week.  You can have
>> the fastest machine on the world and Windoze always manages to bring
>> it down to a slowness we wouldn't have accepted even 20 years ago.
>
> This is mainly an artifact of Windows updates destroying locality of
> data pretty fast and mainly a problem when running on spinning rust.
> DLLs and data files needed for booting or starting specific
> software become spread wide across the hard disk. Fragmentation isn't
> the issue here - NTFS is pretty good at keeping it low. Still, the
> right defragmentation tool will help you:

You can't very well defragment the disk while updates are being
performed.  Updating goes like this:


+ install from an installation media

+ tell the machine to update

+ come back next day and find out that it's still looking for updates or
  trying to download them or wants to be restarted

+ restart the machine

+ start over with the second step until all updates have been installed


That usually takes a week.  When it's finally done, disable all
automatic updates because if you don't, the machine usually becomes
unusable when it installs another update.

It doesn't matter if you have the fastest machine on the world or some
old hardware you wouldn't actually use anymore, it always takes about a
week.

> I always recommend staying away from the 1000 types of "tuning tools",
> they actually make it worse and take away your chance of properly
> optimizing the on-disk file layout.

I'm not worried about that.  One of the VMs is still on an SSD, so I
turned off defragging.  The other VMs that use files on a hard disk
defrag themselves regularly over night.

> And I always recommend using MyDefrag and using its system disk
> defrag profile to reorder the files in your hard disk. It takes ages
> the first time it runs but it brings back your system to almost out of
> the box boot and software startup time performance.

That hasn't been an issue with any of the VMs yet.

> It uses some very clever ideas to place files into groups and into
> proper order - other than using file mod and access times like other
> defrag tools do (which even make the problem worse by doing so because
> this destroys locality of data even more).

I've never heard of MyDefrag, I might try it out.  Does it make updating
any faster?

> But even SSDs can use _proper_ defragmentation from time to time for
> increased lifetime and performance (this is due to how the FTL works
> and because erase blocks are huge, I won't get into detail unless
> someone asks). This is why mydefrag also supports flash optimization.
> It works by moving as few files as possible while coalescing free space
> into big chunks which in turn relaxes pressure on the FTL and allows to
> have more free and continuous erase blocks which reduces early flash
> chip wear. A filled SSD with long usage history can certainly gain back
> some performance from this.

How does it improve performance?  It seems to me that, for practical
use, almost all of the better performance with SSDs is due to reduced
latency.  And IIUC, it doesn't matter for the latency where data is
stored on an SSD.  If its performance degrades over time when data is
written to it, the SSD sucks, and the manufacturer should have done a
better job.  Why else would I buy an SSD.  If it needs to reorganise the
data stored on it, the firmware should do that.