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Hello,
We release the beta in the hope to receive some feedback. The final version will probably contain more new features (that are not so difficult to implement.)
I'll add some explanatory remarks to the advanced features that come with this release.
The version is available at http://www.resco.net/palm/backup/downloads.asp
Best regards
Flushing DbCache
(The functionality works only on NVFS devices.) DbCache serves as a swapping area for databases and their records. DbCache gets filled as more databases are read. As any backup must necessarily read complete RAM contents, DbCache gets always filled. The fact of filling the DbCache theoretically does not mean much, yeat in praxis there are some negative consequences:
- The overall responsiveness of the PDA might decrease.
- DbCache fragmentation can increase. (Even if the backup itself does not contribute to the fragmentation,
PDA with full DbCache can easier get fragmented later.) RscBackup has several tools dealing with the DbCache:
- RAM Info dialog offers "Flush DbCache" button.
- Both manual and scheduled backup can flush the DbCache after they complete its work. Notice that flushing DbCache after scheduled backup must yield better results. The reason is that the scheduled backup loads only small part of the RscBackup application (1st segment), while RscBackup GUI requires loading of several records that are locked and placed in various memory parts, increasing thus the fragmentation. Warning:
There is a general misunderstanding among the Palm users that clearing the DbCache can increase the PDA stability. The ratio behind this statement is this:
Most stability problems are caused by the background applications that forget to lock itself in the memory. If this happens and the DbCache gets filled, the OS may decide (at its own discretion) to purge some of the unlocked records. If it by chance decides to purge the background application, a crash is inevitable.
BUT: Flushing the DbCache cannot help in this respect. It either has no influence or will the problem even aggravate.
Prevent DbCache Fragmentation
(The option works only on NVFS devices and can be set for both manual and scheduled backups.)
This option tries to solve the problem of the DbCache fragmentation, which often prevents from working apps that need large contiguous storage block. (Large means the order of magnitude 1 MB or more.)
Because Palm apps are traditionally limited to the 64K record size, there are just a few apps using that large blocks, yet they are quite popular - e.g. Blazer or Tom Tom. How the fragmentation occurs:
Locked records create non-movable islands in the DbCache. Fragmentation occurs when the locked records are evenly distributed within the DbCache so that the free space among them is relatively small. What does RscBackup:
If there is enough storage RAM, RscBackup will try to reserve large memory block during backup and release it afterwards. Warning:
At the moment of this writing the influence of this setting is not sufficiently tested. While it really decreases the fragmentation, it may cause also backup (verify, diff) slow-down.
Disable notifications
(The option can be set for both manual and scheduled backups.)
This is another advanced option aiming on stability problems.
Technically the option prevents OS from broadcasting frequently used notifications. Unfortunately, not all notifications can be blocked this way - mainly because some of them are vital for the OS functionality. The idea behind is that if these notifications are suppressed, background applications will not be activated and hence they cannot crash. In the optimal case this will delay the crash of the ill-behaving background application to the moment when the notifications are re-enabled. Because this happens only after backup completion, the user gets at least a safe backup set. (If the crash could not be prevented.) Use in cases when you get crashes that cannot be cured by other means.
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