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show system virtual-memory

 

List of Syntax

Syntax

Syntax (EX Series)

Syntax (TX Matrix Router)

Syntax (TX Matrix Plus Router)

Syntax (MX Series Router)

Syntax (QFX Series)

Syntax (Junos OS Evolved)

Syntax

Syntax (EX Series)

Syntax (TX Matrix Router)

Syntax (TX Matrix Plus Router)

Syntax (MX Series Router)

Syntax (QFX Series)

Syntax (Junos OS Evolved)

Release Information

Command introduced before Junos OS Release 7.4.

Command introduced in Junos OS Release 9.0 for EX Series switches.

sfc option introduced for the TX Matrix Plus router in Junos OS Release 9.6.

Command introduced in Junos OS Release 11.1 for the QFX Series.

Command introduced in Junos OS Release 14.1X53-D20 for the OCX Series.

node option introduced in Junos OS Evolved Release 18.3R1.

Description

Display the usage of Junos OS kernel memory listed first by size of allocation and then by type of usage. Use the show system virtual-memory command for troubleshooting with Juniper Networks Customer Support.

Options

noneDisplay kernel dynamic memory usage information.
all-chassis(TX Matrix routers and TX Matrix Plus routers only) (Optional) Display kernel dynamic memory usage information for all chassis.
all-lcc(TX Matrix routers and TX Matrix Plus routers only) (Optional) On a TX Matrix router, display kernel dynamic memory usage information for all T640 routers connected to the TX Matrix router. On a TX Matrix Plus router, display kernel dynamic memory usage information for all connected T1600 or T4000 LCCs.
all-members(EX4200 switches and MX Series routers only) (Optional) Display kernel dynamic memory usage information for all members of the Virtual Chassis configuration.
infrastructure name(QFabric systems only) (Optional) Display kernel dynamic memory usage information for the fabric control Routing Engine and fabric manager Routing Engine.
interconnect-device name(QFabric systems only) (Optional) Display kernel dynamic memory usage information for the Interconnect device.
lcc number(TX Matrix routers and TX Matrix Plus routers only) (Optional) On a TX Matrix router, display kernel dynamic memory usage information for a specific T640 router that is connected to the TX Matrix router. On a TX Matrix Plus router, display kernel dynamic memory usage information for a specific router that is connected to the TX Matrix Plus router.

Replace number with the following values depending on the LCC configuration:

  • 0 through 3, when T640 routers are connected to a TX Matrix router in a routing matrix.

  • 0 through 3, when T1600 routers are connected to a TX Matrix Plus router in a routing matrix.

  • 0 through 7, when T1600 routers are connected to a TX Matrix Plus router with 3D SIBs in a routing matrix.

  • 0, 2, 4, or 6, when T4000 routers are connected to a TX Matrix Plus router with 3D SIBs in a routing matrix.

local(EX4200 switches and MX Series routers only) (Optional) Display kernel dynamic memory usage information for the local Virtual Chassis member.
member member-id(EX4200 switches and MX Series routers only) (Optional) Display kernel dynamic memory usage information for the specified member of the Virtual Chassis configuration. For EX4200 switches, replace member-id with a value from 0 through 9. For an MX Series Virtual Chassis, replace member-id with a value of 0 or 1.
node node-name(Junos OS Evolved only) (Optional) Display the kernel memory information for the specified node. If no node is specified, information is displayed for all nodes.
node-group name(QFabric systems only) (Optional) Display kernel dynamic memory usage information for the Node group.
scc(TX Matrix routers only) (Optional) Display kernel dynamic memory usage information for the TX Matrix router (or switch-card chassis).
sfc number(TX Matrix Plus routers only) (Optional) Display kernel dynamic memory usage information for the TX Matrix Plus router. Replace number with 0.

Additional Information

By default, when you issue the show system virtual-memory command on the master Routing Engine of a TX Matrix router or a TX Matrix Plus router, the command is broadcast to all the master Routing Engines of the LCCs connected to it in the routing matrix. Likewise, if you issue the same command on the backup Routing Engine of a TX Matrix or a TX Matrix Plus router, the command is broadcast to all backup Routing Engines of the LCCs that are connected to it in the routing matrix.

Note

The show system virtual-memory command with the | display XML pipe option now displays XML output for the command in the parent tags: <vmstat-memstat-malloc>, <vmstat-memstat-zone>, <vmstat-sumstat>, <vmstat-intr>, and <vmstat-kernel-state> with each child element as a separate XML tag. In Junos OS Releases 10.1 and earlier, the | display XML option for this command does not have an XML API element and the entire output is displayed in a single <output> tag element.

Required Privilege Level

view

List of Sample Output

show system virtual-memory

show system virtual-memory (Junos OS Evolved without node specified)

show system virtual-memory scc (TX Matrix Router)

show system virtual-memory sfc (TX Matrix Plus Router)

show system virtual-memory | display xml

show system virtual-memory (QFX Series)

Output Fields

Table 1 lists the output fields for the show system virtual-memory command. Output fields are listed in the approximate order in which they appear.

Table 1: show system virtual-memory Output Fields

Field Name

Field Description

Memory statistics by bucket size

Size

Memory block size (bytes). The kernel memory allocator appropriates blocks of memory whose size is exactly a power of 2.

In Use

Number of memory blocks of this size that are in use (bytes).

Free

Number of memory blocks of this size that are free (bytes).

Requests

Number of memory allocation requests made.

HighWater

Maximum value the free list can have. Once the system starts reclaiming physical memory, it continues until the free list is increased to this value.

Couldfree

Total number of times that the free elements for a bucket size exceed the high-water mark for that bucket size.

Memory usage type by bucket size

Size

Memory block size (bytes).

Type(s)

Kernel modules that are using these memory blocks. For a definition of each type, refer to a FreeBSD book.

Memory statistics by type

Type

Kernel module that is using dynamic memory.

InUse

Number of memory blocks used by this type. The number is rounded up.

MemUse

Amount of memory in use, in kilobytes (KB).

HighUse

Maximum memory ever used by this type.

Limit

Maximum memory that can be allocated to this type.

Requests

Total number of dynamic memory allocation requests this type has made.

Type Limit

Number of times requests were blocked for reaching the maximum limit.

Kern Limit

Number of times requests were blocked for the kernel map.

Size(s)

Memory block sizes this type is using.

Memory Totals

In Use

Total kernel dynamic memory in use (bytes, rounded up).

Free

Total kernel dynamic memory free (bytes, rounded up).

Requests

Total number of memory allocation requests.

ITEM

Kernel module that is using memory.

Size

Memory block size (bytes).

Limit

Maximum memory that can be allocated to this type.

Used

Number of memory blocks used by this type. The number is rounded up.

Free

Number of memory blocks available to this type.

Requests

Total number of memory allocation requests this type has made.

interrupt

Timer events and scheduling interruptions.

total

Total number of interruptions for each type.

rate

Interruption rate.

Total

Total for all interruptions.

Sample Output

show system virtual-memory

user@host> show system virtual-memory

Note: Kernel direct memory map only displays for the 64-bit platform.

show system virtual-memory (Junos OS Evolved without node specified)

user@host> show system virtual-memory

show system virtual-memory scc (TX Matrix Router)

user@host> show system virtual-memory scc

show system virtual-memory sfc (TX Matrix Plus Router)

user@host> show system virtual-memory sfc 0

show system virtual-memory | display xml

user@host> show system virtual-memory | display xml

Note: <kernel-direct-mm-size-information> only displays for 64 bit platform.

show system virtual-memory (QFX Series)

user@switch> show system virtual-memory | display xml