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twelveeighty

Member

From: Alberta, Canada

Registered: 2011-09-04

Posts: 1,096

Eclipse 4.8 Photon causes extreme Virtual size when using Webkit

Eclipse in [community] is still in 4.7.3a, but when running Eclipse 4.8 as installed from the official download page, I noticed something strange when I inspect the processes spawned:

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                           
 5530 twelvee+  20   0  102.4g 703.5m  74.5m S   1.7   4.4   1:28.76 java                                              
 5766 twelvee+  20   0  114.0g  72.5m  60.0m S   0.0   0.5   0:00.37 WebKitWebProces                                   
 5768 twelvee+  20   0   98.0g  43.9m  30.9m S   0.0   0.3   0:00.16 WebKitNetworkPr                                   

I understand that Virtual size isn't actual memory usage, but the numbers reported are several times the total size used on my root partition (25 GB), which seems obscene to me?

This must have something to do with WebKit. On launching Eclipse, the java process reports much lower Virtual size: around 5301m. As soon as I hover the mouse over a class and wait for the Javadoc window to open, it immediately jumps to over 100g and the other two WebKit* processes spawn. I have both webkit2gtk (2.20.3-1) and qt5-webkit (5.212.0alpha2-18) installed.

I tried disabling the Webkit renderer, but neither of the following options seems to have any effect in 4.8 Photon:

-Dorg.eclipse.swt.browser.DefaultType=mozilla
-Dorg.eclipse.swt.browser.UseWebKitGTK=false

I guess my real question is: is the Virtual size reported cause for concern, or should I just live with it? If it is a problem, does anyone know how to turn off the Webkit stuff in 4.8 Photon?

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,657

Re: Eclipse 4.8 Photon causes extreme Virtual size when using Webkit

The following may help in interpreting process level memory values displayed as scalable columns and discussed under topic `3a. DESCRIPTIONS of Fields'.

          %MEM - simply RES divided by total physical memory
          CODE - the `pgms' portion of quadrant 3
          DATA - the entire quadrant 1 portion of VIRT plus all
                 explicit mmap file-backed pages of quadrant 3
          RES  - anything occupying physical memory which, beginning with
                 Linux-4.5, is the sum of the following three fields:
                 RSan - quadrant 1 pages, which include any
                        former quadrant 3 pages if modified
                 RSfd - quadrant 3 and quadrant 4 pages
                 RSsh - quadrant 2 pages
          RSlk - subset of RES which cannot be swapped out (any quadrant)
          SHR  - subset of RES (excludes 1, includes all 2 & 4, some 3)
          SWAP - potentially any quadrant except 4
          USED - simply the sum of RES and SWAP
          VIRT - everything in-use and/or reserved (all quadrants)

This value is the amount of memory that might potentially get used given that ALL resources related to that process (including all the libraries it links to (naturally it jumps up because it starts to load in all relevant libs for webkit), files it references etc.) were to decide to use the memory they requested to the fullest at the same time. If that's a situation that arises, you have much worse problems than spawning webkit process in your eclipse window.

Too long, didn't read: No, this doesn't matter.

Last edited by V1del (2018-07-09 16:56:46)