Is this a memory leak?
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Hi,
i'm working on an Qt project wit 4.8.5 on an small ARM5 device.
My valgrind check did not report any memory leaks but if i check the free memory at the device with "top" I see the value decreasing every ~1Minute with 28k?
If my application is not running the free memory is const.
The "top" is showing a constant VSZ value for my app. Only the free mem is going less....
Is it possible that qt will free this memory if necessary or is this a job from the linux?
Thank you
Ferdl -
Hi @Ferdl, and welcome :)
At a guess, I'd say this is not memory that Qt is holding onto, but rather some sort additional memory utilisation being done by the kernel for system optimization (not necessarily for your app). Consider, for example, that any truly free / empty RAM is wasted RAM, in that the kernel can always be using it to cache things :)
Anyway, I'd try looking at something like the output of:
cat /proc/meminfo
to get a more specific idea of where the memory is going. But at this stage, it doesn't sound like anything to worry about... yet... ;)
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thanks Paul for this tip
I checked the meminfo and compared two readouts after a few minutes:
MemTotal: 117768 117768
MemFree: 40908 40544
MemAvailable: 87776 87800
Buffers: 17716 18096
Cached: 30152 30156
SwapCached: 0 0
Active: 22532 23144
Inactive: 42628 42404
Active(anon): 17492 17500
Inactive(anon): 304 300
Active(file): 5040 5644
Inactive(file): 42324 42104
Unevictable: 0 0
Mlocked: 0 0
SwapTotal: 0 0
SwapFree: 0 0
Dirty: 56 0
Writeback: 0 0
AnonPages: 17320 17324
Mapped: 13424 13424
Shmem: 504 504
Slab: 7564 7568
SReclaimable: 4628 4632
SUnreclaim: 2936 2936
KernelStack: 464 464
PageTables: 488 488
NFS_Unstable: 0 0
Bounce: 0 0
WritebackTmp: 0 0
CommitLimit: 58884 58884
Committed_AS: 78844 78844
VmallocTotal: 892928 892928
VmallocUsed: 964 964
VmallocChunk: 876444 876444the main difference I see is the Active and Inactive (anon and file) values.
I will search for some explanation for that meaning..... I think you are right actually it looks ok....
please corect me if I'm wrong :)have a good day