目标c – UILabel分配持续并占用8Mb的内存

主视图具有嵌入在导航控制器中的单个视图控制器.

我刚刚通过一个分配检查,并注意到,通过这种单一视图加载消耗大约10MB的内存,其中8MB是这些标签,当我进入下一个视图,该分配仍然存在.

可能是什么原因造成的？

这是记录分配的快照.

Snapshot    Timestamp   Growth  # Persistent
 VM: UILabel (CALayer)      7.90 MB 10
  0x5417000 00:02.950.428   1.23 MB  
  0x5553000 00:02.967.675   1.23 MB  
  0x568f000 00:02.978.283   1.23 MB  
  0x591d000 00:03.013.095   832.00 KB    
  0x57cb000 00:03.004.334   832.00 KB    
  0x50a7000 00:02.919.040   832.00 KB    
  0x5177000 00:02.937.076   832.00 KB    
  0x5347000 00:02.940.969   832.00 KB    
  0x52d3000 00:02.998.823   120.00 KB    
  0x52f1000 00:03.023.068   16.00 KB

这是第一个堆栈跟踪,其余的是相同的：

0 libsystem_kernel.dylib mach_vm_allocate
   1 libsystem_kernel.dylib vm_allocate
   2 QuartzCore CA::Render::Shmem::new_shmem(unsigned long)
   3 QuartzCore CA::Render::Shmem::new_bitmap(unsigned int,unsigned int,unsigned int)
   4 QuartzCore CABackingStoreUpdate_
   5 QuartzCore ___ZN2CA5Layer8display_Ev_block_invoke
   6 QuartzCore x_blame_allocations
   7 QuartzCore CA::Layer::display_()
   8 QuartzCore CA::Layer::display_if_needed(CA::Transaction*)
   9 QuartzCore CA::Layer::layout_and_display_if_needed(CA::Transaction*)
  10 QuartzCore CA::Context::commit_transaction(CA::Transaction*)
  11 QuartzCore CA::Transaction::commit()
  12 UIKit -[UIApplication _reportAppLaunchFinished]
  13 UIKit -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:]
  14 UIKit -[UIApplication handleEvent:withNewEvent:]
  15 UIKit -[UIApplication sendEvent:]
  16 UIKit _UIApplicationHandleEvent
  17 GraphicsServices _PurpleEventCallback
  18 GraphicsServices PurpleEventCallback
  19 CoreFoundation __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__
  20 CoreFoundation __CFRunLoopDoSource1
  21 CoreFoundation __CFRunLoopRun
  22 CoreFoundation CFRunLoopRunSpecific
  23 CoreFoundation CFRunLoopRunInMode
  24 UIKit -[UIApplication _run]
  25 UIKit UIApplicationMain
  26 main 
  27 libdyld.dylib start

解

以为我会分享我如何设法减少这个.事实证明,如果你有标签,其中包含字词,并且在两边和顶部和底部都有大量的空白空间,这会增加显示它们所需的内存.因此,解决方案是将该空间减少到绝对最小值.

以下是生成的快照：

Snapshot    Timestamp   Growth  # Persistent
 VM: UILabel (CALayer)      2.37 MB 9
  0x5321000 00:02.503.255   208.00 KB    
  0x5248000 00:02.474.045   392.00 KB    
  0x5087000 00:02.432.317   208.00 KB    
  0x50bb000 00:02.445.927   64.00 KB     
  0x5303000 00:02.498.137   120.00 KB    
  0x52aa000 00:02.481.354   292.00 KB    
  0x50cb000 00:02.449.625   180.00 KB    
  0x5355000 00:02.505.638   112.00 KB    
  0x50f9000 00:02.455.350   848.00 KB