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Old 25th July 2008
Darwimy Darwimy is offline
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Quote:
Originally Posted by JMJ_coder View Post
what is SLC and MLC and why is one better than the other? Also, how do I tell which one a particular card employs?

What do these two do ('noatime' and circular log files)?
Phoenix described the differences between SLC and MLC well. Only a few manufactures provide information which type the use. Transcend usally prints it on their packaging, but not always in the datasheet.

Circular log files are a patch (http://software.wwwi.com/syslogd/) for standard syslogd by which it supports log files which have a fixed size and 'turn over' (start from the beginning) if the end is reached. I find this very useful for use placing logfiles on small ram-disk. The drawback is that these files can only be viewed by a special program ('clog') which understands the file format.
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Old 25th July 2008
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vermaden vermaden is offline
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@JMJ_coder

Yes this is generally a good idea, but considering limited life of flash you have to remember about these things:
- disable SWAP
- mount /tmp in RAM
- mount /var/tam in RAM
- disable all useless logging in /var/log (by config or by links to /dev/null if you are lazy)
- or even mount /var/log in RAM

Quote:
Originally Posted by BSDfan666 View Post
While this is a neat idea.. CF cards are considerably slower then their IDE/SATA counterparts.
That depends on CF you use, there are CF's like Corsair Votager, Buffalo, OCZ Rally2 or Patriot Exporter which provide constant 24MB/s write + 32MB/s read with about 0.1-0.9 ms random access time.

Single drive may not be as fast as harddrive, but RAID0 of 2-4 or even RAID5 of them would give you constant 80MB/s write + 120MB/s read with about 1ms RAT which is comparable to today's SSD's.

It would be very easy do do such thing, 1 even slow CF for / + software RAID0/5 in 4 fast CF's.

You may wath some performance tests of CF's here:
http://www.xbitlabs.com/articles/mem...h-roundup.html
http://www.xbitlabs.com/articles/mem...oundup_11.html
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Old 25th July 2008
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Quote:
Originally Posted by vermaden View Post
or even mount /var/log in RAM
Depending upon the usage, it may be in order to redirect some logs to a remote syslogd server. See the syslogd(8) manpage for details.
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Old 25th July 2008
Darwimy Darwimy is offline
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Quote:
Originally Posted by vermaden View Post
- mount /tmp in RAM
- mount /var/tam in RAM
- disable all useless logging in /var/log (by config or by links to /dev/null if you are lazy)
- or even mount /var/log in RAM
FreeBSD 6 and 7 automatically mount /tmp and /var as a ram-disks if they are not writeable, e.g. if you mount '/' read-only and have not placed them on separate file systems. For /var even the necessary directories are created automatically. However, with the default options this will hide the 'real' /var/db/pkg and you will not see your installed packages.
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Old 25th July 2008
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Quote:
Originally Posted by ocicat View Post
Yes, these blog entries reference an old version of OpenBSD, but recent traffic on misc@ has pointed that they are still valid. I used them as a reference when configuring a 4GB Eee PC to run OpenBSD-current.

FWIW.
I use them too. current and a 4GB Microdrive on a PC Engines Wrap.
The recommendations will not be outdated for the next few years I think.
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Old 27th July 2008
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I just use a 2GB CF for the / kernel and /bin stuff, which gets read often but not written that much often... the rest /var/log, /usr and /home on a real Raptor 10'000 RPM hard drive, it has been working fine for me.
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Old 31st July 2008
JMJ_coder JMJ_coder is offline
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Hello,

I have finally gotten around to testing this setup. I must say that I am disappointed verily!

The first issue is that it wouldn't install from the CD. I could the CD to boot and run the installation, but when it went to copy the packages, it panicked. I resolved this by installing over http (the first time I did this - it was fun! ). I think the issue was that the CD and the card were on the same IDE cable - and I read that that could cause some issues.

Then, unpacking pkgsrc took over 7 hours (that's when I went to sleep for the night). When I left it, it was only up to misc. Compiling took a very long time - it reminded me of when I was using the GENERIC kernel on my dual-core system. See here.

It is also very sluggish when trying to multi-task.

This may be a little unfair. The card I used was an Ultra II - 9MB/s write, 10MB/s read. I also don't think it supports UDMA. I used it because I got it on the cheap during a sale.

I am thinking of giving it another shot with an Extreme III card. The new ones are rated at 30MB/s (I hope this isn't just in the software for Windows ). Does anyone know if the Extreme III from SanDisk is capable of UDMA (anything special to get it going - or is it just there), and if it makes use of SLC?
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