[j-nsp] High RE memory utilization for JUNOS 7.6 and latter

[Ihsan Junaidi Ibrahim]

Hi all,

Is there any reason why on 7.6 and above, the RE memory utilization can
shoot up to more than 90%. As a comparison, I have a number of systems
running 7.0 with multiple BGP full feeds w/ 512 MB RAM (RE 3.0) and the
utilization rarely exceed 70%.

I have 3 systems with 7.6 and 8.1 (512 MB RAM, RE 3.0, 2 BGP full feeds)
behaving this way. I've referred to JTAC but truthfully, they haven't been
much of a help. :(

7.6
--
ihsan at GLSFB_ROC7_007> show task memory 
Memory                 Size (kB)  %Available  When
  Currently In Use:       189534         44%  now
  Maximum Ever Used:      224850         52%  06/11/29 07:47:55
  Available:              427360        100%  now

ihsan at GLSFB_ROC7_007> show chassis routing-engine | match Memory   
    Memory utilization          95 percent

ihsan at GLSFB_ROC7_007> show route summary 
Autonomous system number: 9930
Router ID: 203.121.16.9

inet.0: 207600 destinations, 442762 routes (207470 active, 0 holddown, 244
hidden)
              Direct:     10 routes,     10 active
               Local:      9 routes,      9 active
                OSPF:    677 routes,    673 active
                 BGP: 442065 routes, 206777 active
              Static:      1 routes,      1 active

8.1
--
ihsan at GLSFB_ROC7_007> ihsan at glsfb3-mbone> show task memory 
Memory                 Size (kB)  %Available  When
  Currently In Use:       163078         37%  now
  Maximum Ever Used:      170439         39%  06/11/16 21:19:51
  Available:              432910        100%  now

ihsan at glsfb3-mbone> show chassis routing-engine | match Memory    
    Memory utilization          90 percent 

Autonomous system number: 9930
Router ID: 10.254.250.17

inet.0: 207609 destinations, 414487 routes (207609 active, 0 holddown, 0
hidden)
              Direct:      4 routes,      4 active
               Local:      2 routes,      2 active
                OSPF:    723 routes,    722 active
                 BGP: 413758 routes, 206881 active

7.0
--
ihsan at GLSFB_ROC7_006> show task memory      
Memory                 Size (kB)  %Available  When
  Currently In Use:       194327         44%  now
  Maximum Ever Used:      203735         46%  06/12/02 01:49:01
  Available:              438411        100%  now

ihsan at GLSFB_ROC7_006> show chassis routing-engine | match Memory 
    Memory utilization          63 percent

ihsan at GLSFB_ROC7_006> show route summary 
Autonomous system number: 9930
Router ID: 203.121.16.6

inet.0: 207595 destinations, 500182 routes (207465 active, 0 holddown, 258
hidden)
              Direct:      7 routes,      7 active
               Local:      6 routes,      6 active
                OSPF:    680 routes,    677 active
                 BGP: 499489 routes, 206775 active

---
Thank you for your time,
Ihsan Junaidi Ibrahim