Thanks Bob and Dianne, The issue is that I have no choice but do a lot of writing since this is a research app that constantly logs phone and user activity over many months... We are dealing ok with battery and processing power (we only write every several minutes), and the main concern remains the Flash lifetime.
We are working with cyclic log files (that roll over every several hours), and have already found a way to move our older files to the SD card. However our current dilemma is whether to do all writing on the SD-card, or keep the "current" open file on the main memory, and copy it to SD when moving to the next log file. The problem of doing everything on the SD card is that when a user mounts the card to a PC, we can't access it for logging and other tasks, and that leads to various crashes and issues, so I thought it might be simpler if we work with the "current" file on the main memory, but I fear the Flash degradation... I'm willing to buy new SD cards every few months, but I really don't want to mess up the phone itself! On Apr 4, 2:27 am, Dianne Hackborn <[email protected]> wrote: > If you are talking about internal storage (not RAM memory), then yes this is > generally flash memory, and you want to be careful about how much you write > to it for numerous reasons: also extremely important are the battery impact > (writing to flash is expensive) and performance (causing other things that > are accessing flash storage to be blocked by what you are doing). > > That said, properly designed flash storage won't let you write to the same > block over and over. Writes are spread across the flash storage just to > avoid that kind of issue. > > > > On Sat, Apr 3, 2010 at 9:49 AM, Nadav <[email protected]> wrote: > > Hi All, > > > I'm wondering how worried should I be about writing an app that does a > > lot of writing (logs + db files) to the phone's main memory. > > > In the past I was involved in a project that had to do a lot of > > writing to SD card, and the SD cards started malfunctioning after 2-3 > > months due to this, and had to be replaced every now and then. The > > developer realized he was reaching the flash memory's read/write > > guarantees (don't remember the exact specs). > > > If the phone's main memory is also flash based, should this be a > > concern? I wouldn't want to damage the phone's memory in a permanent > > way.... > > > I'm also not sure if the issue is related to reading writing to the > > same physical block (the guy was using a single log file and kept > > appending it, so he was constantly accessing the file's header block), > > and whether writing cyclic log files might remedy a problem like > > this.. > > > Would appreciate any thoughts on this issue. > > > Thanks! > > > -- > > You received this message because you are subscribed to the Google > > Groups "Android Developers" group. > > To post to this group, send email to [email protected] > > To unsubscribe from this group, send email to > > [email protected]<android-developers%[email protected]> > > For more options, visit this group at > >http://groups.google.com/group/android-developers?hl=en > > > To unsubscribe, reply using "remove me" as the subject. > > -- > Dianne Hackborn > Android framework engineer > [email protected] > > Note: please don't send private questions to me, as I don't have time to > provide private support, and so won't reply to such e-mails. All such > questions should be posted on public forums, where I and others can see and > answer them. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
