I tried searching for an answer to my question, but I'm having a difficult time formulating the question correctly.

My desktop PC runs Windows 7 from an OCZ Agility 2 SSD. There are no other drives in the machine. All of my household's files are stored on an unraid server I built years ago. My wife and I recently had our first child, and the large number of digital photos we're creating, and their value, mean I'm backing them up routinely. I'm just copying them all from the unraid server, over my lan, to an external USB HDD connected to my Windows 7 desktop.

I am not interested in whether SSD write endurance is a practical problem or not. I an simply trying to determine: is my desktop's SSD is written to when copying from a network share to an external HDD?. This is probably more an OS issue than a hardware issue, but it's still storage related so I posted it here.

No, the OS drive would not be involved.

Using explorer or a command prompt: No*. Using a third party copy tool: Ask them.

* Copying big files with low RAM in your system may cause swapping.

I'll answer the question in bold, not the title.
Like you said, formulation issues (temporary data and cached data are different things).

Short answer:
In general, no it shouldn't.
However you should test this kind of thing if you really care. Doesn't your drive have a usage counter you can check with SMART?

Long answer:
It's probably more of a configuration issue than strictly a OS issue. Any OS should cache this sort of data in RAM, not on the system drive.
I think Windows can be configured to cache to disk however. But probably to a dedicated partition rather than to the system drive. Look it up.
EDIT: washu beat me to the other caveats
Again: it should be easy enough to test.


Finally, you may not be interested but...
a) you should consider backing up data you care about offsite
b) but backing up a huge amount of data offsite can be costly and aggravating
c) the value of full-res pics to you is probably only marginally higher than the value of much smaller files with a lower resolution
d) and maybe the grandparents or other relatives might like to have (many of) these pics anyway (the Torvalds backup strategy - BitTorrent is a convenient and reliable tool for it)

Thanks all - appreciate it.

Thanks for the terminology correction: cache vs temp. My desktop has 8 GB of RAM. Caching to RAM is expected, but I wasn't sure. As far as testing: while crafting robocopy batch scripts, my desktop's HDD led wasn't blinking more than ordinary. That "test" suggests that the local SSD isn't caching.

About my backup plan ... I have a pair of 1TB external drives; one travels off-site.

Aside: I've been really happy with the drives - they're Toshiba Canvio Slim USB3 externals. USB3 is a dream coming from USB2.0, and they're powered over USB for less cable clutter.

Coincidentally, they're Newegg's 1pm shell-shocker today:

http://www.newegg.com/Special/ShellShoc ... 12232013_3

Hi, run 'resmon' (Resource Monitor) while you're running the copy and it will show you the activity in your system. The disk tab even lists the file names involved in activity.

Seb

Nice! I will definitely examine this next time.


Just to continue the off-site discussion, has anyone used Crashplan's free 'cloud' backup solution?

https://www.code42.com/crashplan/features/compare/

Similar to HFat's point 'd' above, but using CrashPlan's software instead of BitTorrent. Instead of backing up to CrashPlan's servers, you backup to some other PC that you or someone you know owns. The free version still permits encryption with user-generated keys, and scheduling. Many of my friends with small children have expressed interest in this sort of cooperative cloud backup. I have only limited experience with bittorrent and my friends have zero, so I'd need to keep this as simple as possible. And none of will have any free time for the next 16-18 (+) years! The initial backup set would take a while ... but followup incrementals would be reasonable.

I have used it an it works well. It is a great "set it and forget it" type solution. At a previous job I was able to use my work PC with a big external drive as a remote destination. When that no longer was an option I started paying for their cloud storage and it works fine as well.

You can make the initial backup locally then transfer the backup archive to the remote location so you don't have to backup everything over the internet. This saves a lot of time and bandwidth. It took a couple of months to do the initial backup once I switched to cloud storage.

Some issues:
- The free version only allows one backup set. I like to have different things backed up to different locations depending on importance, but that may not be an issue for many. You can still back up to multiple locations simultaneously. You can have a local backup and a remote friend, or two friends etc.

- The client is extremely memory hungry. It is written in Java, which speaks for itself. If you have a big backup set you may need to manually increase the amount of memory the JVM is allowed to use. If you have a machine with low memory then Crashplan is not for you. 8+ GB is fine. 4 GB on a lightly used machine will do. Less than 4 GB is not going to be usable unless it is a dedicated file/backup server that doesn't get used as a desktop.

- The backups are not stored as usable files. You must have Crashplan to recover. If Crashplan goes out of business your backups are useless. It is good as part of a backup solution, don't use it as your only backup.