RE: [squid-users] Using null fs

yeah thats true. but IMOP, using null fs and holding those object in RAM
"should" give a better squid performance or maybe a good hit rate since
squid functions the same way as having a null fs or having a big cache_dir
except no IO bound problems (since this is the hindrance). I asked this coz
i have seen on cachemgr that only have 10%-19% hit rate using null fs (with
250MB cache_mem)compared to 25%-45% using cache_dir (with 250MB cache_mem).

so as you can see, only the cache_mem is different, so why null fs will have
lower hit rate compared to aufs, or diskd fs since holding those objects in
RAM is the same holding them on disk except that using null fs will
eventually be lost on reboot.

hope you can enlighten me up a bit.

-----Original Message-----
From: Adam Aube [mailto:aaube@firstindependent.net]
Sent: Tuesday, August 05, 2003 6:13 AM
To: 'squid-mailing list'
Subject: RE: [squid-users] Using null fs

> will null fs with a cache_mem of 250MB could give me a
> higher hit rate compared to a 250MB cache_mem with a
> 3gig cache_dir, or with a 250MB with a 100MB cache_dir
> since i want to lessen I/O bound operations on squid.

You can usually hold more cache on disk than you can in
memory. Using no disk cache will reduce your hit rate.

Also, every time you restart Squid it will dump its
memory. Since you have no disk cache, Squid will have
to fully rebuild its cache every time it restarts. This
will also reduce your hit rate.

In fairness, you will rarely have to restart Squid.

Adam

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.237 / Virus Database: 115 - Release Date: 3/7/2001
--
This message has been scanned for viruses and
dangerous contents on SSCR Email Scanner Server, and is
believed to be clean.
---
Incoming mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 8/4/2003
---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 8/4/2003
-- 
This message has been scanned for viruses and
dangerous contents on SSCR Email Scanner Server, and is
believed to be clean.