VM heap size doesnt change??

droidkevlar

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So I put the VM heap size from 24m to 32m in CM settings -> Performance and rebooted. When I checked the build.prop, it still says 24m. Is it changed somewhere else and I shouldnt worry about this? Or it should have changed and some reason it isnt for me and I should change it manually? I do rem noticing this since build 141 as that was the first CM build I came onto. Before I used to change it manually as other ROMs I used didnt have that feature. Thanks in advance guys.
 

captdroid

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So I put the VM heap size from 24m to 32m in CM settings -> Performance and rebooted. When I checked the build.prop, it still says 24m. Is it changed somewhere else and I shouldnt worry about this? Or it should have changed and some reason it isnt for me and I should change it manually? I do rem noticing this since build 141 as that was the first CM build I came onto. Before I used to change it manually as other ROMs I used didnt have that feature. Thanks in advance guys.

Using the CyanogenMod Performance Settings does change the VM heap size. I don't know why it still shows as 24m in the build.prop after setting the size in CyanogenMod Settings.
 
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droidkevlar

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So how do you know its changed then? Not calling you a lair, I just want to learn this stuff for myself.
 

captdroid

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So how do you know its changed then? Not calling you a lair, I just want to learn this stuff for myself.

Well because I was having a problem with the My Verizon app with VM heap size set to 24m and I could see this in aLogcat log errors that the VM heap size was to small. Once I set VM heap size to 32m using CyanogenMod Performance Settings no more VM heap size errors. But the build.prop does still show 24m for VM heap size.
 
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captdroid

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So it must be changed somewhere else then, uh?

Yup must be since after selecting the VM heap size in CyanogenMod Performance Settings it's set that way unless changed. I think the build.prop setting is the default on boot but when I reboot the VM heap size is still set to I presume the selection in CM Performance Settings based on the fact My Verizon app still works :)
 
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Droid DOES!!

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Changed mine with Root Explorer and its stuck.

Sent from my Droid using DroidForums app (free in market)
 

meishkov

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I changed it thru root explorer as well. The build.prop file was in /system, which I'm sure you already knew. I still don't know exactly what it does..leaves more free memory available or something?? I have no idea, but I'm always looking for tweaks That I can do to make my phone run at it's best. I'm on SS 4.9 at the moment, and it definitely hasn't seemed to damper anything performance wise. Does it control how much available memory there is when checking in applications, running services?? That's when my phone runs the best..when the red and green are divided right down the middle, or as close as possible.
 

captdroid

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I changed it thru root explorer as well. The build.prop file was in /system, which I'm sure you already knew. I still don't know exactly what it does..leaves more free memory available or something?? I have no idea, but I'm always looking for tweaks That I can do to make my phone run at it's best. I'm on SS 4.9 at the moment, and it definitely hasn't seemed to damper anything performance wise. Does it control how much available memory there is when checking in applications, running services?? That's when my phone runs the best..when the red and green are divided right down the middle, or as close as possible.

Market app and info in the app VM Heap Size: [APP] VM Heap Tool - xda-developers
 

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VM heap size is maximum memory an application can consume; it does *not* mean it's total memory footprint, just how much *data* it can allocate at the same time. Therefore, the more resource-intensive application, the more heap it *requires* to run; this effect is very visible with LWP's and launchers which operate on large amounts of uncompressed bitmaps. Additionally, JIT pretty much requires large VM heap as the basic idea behind just-in-time optimizer is to trade memory efficiency for operating speed. VM heap is also roughly the biggest chunk of per-app virtual memory space that kernel can't "fake", share between multiple apps, silently drop and reload when accessed or do any of the other memory management tricks that allow to squeeze multiple apps that would each require hundreds of megabytes of memory under naive (e.g. DOS-and win95-like) memory allocation schemes into a handful of MBs that are actually available. Since it cannot be made disappear from physical memory to make room for something else without corrupting app state, the more complex apps grow, the more often they have to be killed --or force closed in Android terminology.
 

jerroedr

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VM heap size is maximum memory an application can consume; it does *not* mean it's total memory footprint, just how much *data* it can allocate at the same time. Therefore, the more resource-intensive application, the more heap it *requires* to run; this effect is very visible with LWP's and launchers which operate on large amounts of uncompressed bitmaps. Additionally, JIT pretty much requires large VM heap as the basic idea behind just-in-time optimizer is to trade memory efficiency for operating speed. VM heap is also roughly the biggest chunk of per-app virtual memory space that kernel can't "fake", share between multiple apps, silently drop and reload when accessed or do any of the other memory management tricks that allow to squeeze multiple apps that would each require hundreds of megabytes of memory under naive (e.g. DOS-and win95-like) memory allocation schemes into a handful of MBs that are actually available. Since it cannot be made disappear from physical memory to make room for something else without corrupting app state, the more complex apps grow, the more often they have to be killed --or force closed in Android terminology.

So, i dont speak computer fluently, and while that kindof makes sense... is there a condensed/slightly more simplified version? lol
 

captdroid

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VM heap size is maximum memory an application can consume; it does *not* mean it's total memory footprint, just how much *data* it can allocate at the same time. Therefore, the more resource-intensive application, the more heap it *requires* to run; this effect is very visible with LWP's and launchers which operate on large amounts of uncompressed bitmaps. Additionally, JIT pretty much requires large VM heap as the basic idea behind just-in-time optimizer is to trade memory efficiency for operating speed. VM heap is also roughly the biggest chunk of per-app virtual memory space that kernel can't "fake", share between multiple apps, silently drop and reload when accessed or do any of the other memory management tricks that allow to squeeze multiple apps that would each require hundreds of megabytes of memory under naive (e.g. DOS-and win95-like) memory allocation schemes into a handful of MBs that are actually available. Since it cannot be made disappear from physical memory to make room for something else without corrupting app state, the more complex apps grow, the more often they have to be killed --or force closed in Android terminology.

So, i dont speak computer fluently, and while that kindof makes sense... is there a condensed/slightly more simplified version? lol

Yes, a few posts back I posted a thread link to a app that has info in it that is simplified. Download and install that app. Or click this link: http://www.appbrain.com/app/vm-heap-tool-(root-only)/com.martino2k6.vmheaptool for a description and pictures. Click the first picture in the vm heap tool description for simplified info about vm heap size.
 
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