1. 

   PangOS
   Beta Veteran

   When I use different devices for caching it seems to decrease overall performance gain.

   i.e. I use 1GB RAM for -eBoostr's caching- and a usb flash drive (read speed of about 18MB/sec) using -Readyboost's caching- and I get GREAT Accelerated Ratios (9.2) as compared to Direct access.

   If I add an identical usb flash drive for -eBoostr's caching- the ratio drops to (1.5) *Readyboost off* (2.4) *Readyboost on*.

   Essentially it seems that overall performance is decreased when using a combination of RAM and USB Drive caching.

   My question is:

   Using devices of different speed affects performance? Meaning that more caching is not necessarily better?

   I hope there's clarity on what I'm saying/asking. I'm very sleepy.
   Running Win7 x64 (7100) btw.

   Posted 2 years ago #
2. 

   Robert Persons
   Member

   Just last night I was experimenting with using two flash drives and found some hardware issues that slowed performance.

   Using 320MB RAM cache and a 4GB flash drive with eBoostr I was getting 50MB/sec throughput on the speed test. Just plugging in another flash drive (Not being used by either eBoostr or ReadyBoost) slowed the throughput to 37MB/sec. It also made the PC noticably slower to shutdown and reboot. Both flash drives were in their own slots (not in a hub sharing a slot). The second flash drive wasn't doing anything, just sitting on the bus.

   Although this might be a unique problem with my system, it might be worth mentioning in the eBoostr documentation to alert other users to the potential issue.

   Vista x32 Home Premium, Asus MOBO

   Posted 2 years ago #
3. 

   mikei
   eBoostr Team

   Let me explain a little.

   eBoostr has load balancing mechanism.
   It tries to use most appropriate device during caching.
   So if you have 2 USB devices it is better than 1 (more balancing can be made)
   If you use RAM with USB, files cached in RAM always taken from RAM but other files can go from USB. So it is also better (more files can be cached) than having only one RAM cache.

   But Check Speed may show lower results due to checking algorithm.

   Speed checking done using file list from all cache files active.
   We do random read on these file without and with cache involved.

   So if you have only RAM cache - the cached speed is speed of reading files from RAM
   If you have RAM + USB then cached speed you see is average of RAM speed (same as in example above) and USB speed for files not placed to RAM.

   So then you add USB cache to RAM you still have same speed for file cached in RAM but you have additional speed for other files placed in USB cache.

   Our check speed procedure shows lower numbers for RAM+USB combination than for RAM only, but these results for lareg set on files in the first case.

   Posted 2 years ago #
4. 

   Zeioth
   Member

   Very, very interesting, thank you mikei.

   Posted 2 years ago #
5. 

   mradr
   Member

   I also would like to add a question on to this.... I know your using a "eBoostr has load balancing mechanism" but is that the same as raid? If it isnt... maybe have a way to raid em then build the load balancing mechanism?

   Posted 2 years ago #

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