Contents

Data buffer commands· 1

buffer apply· 1

buffer queue guaranteed· 1

buffer queue shared· 2

buffer total-shared· 3

burst-mode enable· 4

display buffer 4

display buffer usage· 6

 

Data buffer commands

Inappropriate data buffer changes can cause system problems. Before manually changing data buffer settings, make sure you understand its impact on your device. If the system requires large buffer spaces, H3C recommends that you use the burst-mode enable command. The burst-mode enable command and the buffer apply command are mutually exclusive. If you have configured the data buffer by using one command, you must execute the undo form of the command before using the other command.

buffer apply

Use buffer apply to apply manually configured data buffer settings.

Use undo buffer apply to cancel the application.

Syntax

buffer apply

undo buffer apply

Views

System view

Predefined user roles

network-admin

Usage guidelines

After applying manually configured data buffer settings, you cannot directly modify the applied settings. To modify them, you must cancel the application, reconfigure data buffer settings, and reapply the new settings.

Examples

# Apply manually configured data buffer settings.

<Sysname> system-view

[Sysname] buffer apply

buffer queue guaranteed

Use buffer queue guaranteed to set the fixed-area ratio for a queue.

Use undo buffer queue guaranteed to restore the default.

Syntax

buffer egress [ slot slot-number ] cell queue queue-id guaranteed ratio ratio-value

undo buffer egress [ slot slot-number ] cell queue queue-id guaranteed

Default

The fixed-area ratio for a queue is 12.5%, but the default value in the display buffer queue command output is 12%.

Views

System view

Predefined user roles

network-admin

Parameters

egress: Specifies the egress buffer.

slot slot-number: Specifies an IRF member device by its member ID (slot number). If you do not specify an IRF member device, this command applies to all IRF member devices.

cell: Specifies cell resources.

queue-id: Specifies a queue by its ID in the range of 0 to 7.

ratio ratio-value: Specifies the fixed-area ratio in percentage.

Usage guidelines

The fixed-area space for a queue cannot be used by other queues. It is also called the minimum guaranteed buffer.

The sum of fixed-area ratios configured for queues cannot be greater than or equal to 100%. Queues 5, 6, and 7 must have available fixed-area space.

After you set the fixed-area ratios for some queues, the other queues each are assigned an equal share of the remaining part of the fixed area. The display buffer queue command displays the preceding whole number for each assignment result. Therefore, the sum of the ratios for all queues might be less than 100%.

Examples

# Configure queue 0 to use 15% fixed-area space of cell resources in the egress buffer of IRF member device 2.

<Sysname> system-view

[Sysname] buffer egress slot 2 cell queue 0 guaranteed ratio 15

buffer queue shared

Use buffer queue shared to set the maximum shared-area ratio for a queue.

Use undo buffer queue shared to restore the default.

Syntax

buffer egress [ slot slot-number ] cell queue queue-id shared ratio ratio-value

undo buffer egress [ slot slot-number ] cell queue queue-id shared

Default

The maximum shared-area ratio for a queue is 33%.

Views

System view

Predefined user roles

network-admin

Parameters

egress: Specifies the egress buffer.

slot slot-number: Specifies an IRF member device by its member ID (slot number). If you do not specify an IRF member device, this command applies to all IRF member devices.

cell: Specifies cell resources.

queue-id: Specifies a queue by its ID in the range of 0 to 7.

ratio ratio-value: Specifies the maximum shared-area ratio in percentage.

Usage guidelines

By default, all queues have an equal share of the shared area. You can set the shared-area ratio for a queue. The unconfigured queues use the default setting. The shared-area ratio for each queue is finally determined by the chip based on your configuration and the number of packets to be sent.

For the maximum shared-area ratio for a queue, the percentage values 0 to 100 are divided into 10 ranges. Table 1 shows the effective values that correspond to the configured values of ratio-value.

Table 1 Mapping between configured values of ratio-value and effective values

Configured value of ratio-value	Effective value
0 to 1	1
2 to 3	3
4 to 7	6
8 to 16	11
17 to 29	20
30 to 42	33
43 to 60	50
61 to 76	67
77 to 86	80
87 to 100	89

 

Examples

# Configure queue 0 to use up to 5% shared-area space of cell resources in the egress buffer of IRF member device 2.

<Sysname> system-view

[Sysname] buffer egress slot 2 cell queue 0 shared ratio 5

buffer total-shared

Use buffer total-shared to set the total shared-area ratio.

Use undo buffer total-shared to restore the default.

Syntax

buffer egress [ slot slot-number ] cell total-shared ratio ratio-value

undo buffer egress [ slot slot-number ] cell total-shared

Default

The total shared-area ratio is 97% of the buffer.

Views

System view

Predefined user roles

network-admin

Parameters

egress: Specifies the egress buffer.

slot slot-number: Specifies an IRF member device by its member ID (slot number). If you do not specify an IRF member device, this command applies to all IRF member devices.

cell: Specifies cell resources.

ratio ratio-value: Specifies the ratio of the shared area in percentage.

Usage guidelines

After you set the total shared-area ratio, the remaining buffer space is automatically assigned to the fixed area.

Examples

# Configure the shared area to use 65% space of cell resources in the egress buffer of IRF member device 2.

<Sysname> system-view

[Sysname] buffer egress slot 2 cell total-shared ratio 65

burst-mode enable

Use burst-mode enable to enable the Burst feature.

Use undo burst-mode enable to disable the Burst feature.

Syntax

burst-mode enable

undo burst-mode enable

Default

The Burst feature is disabled.

Views

System view

Predefined user roles

network-admin

Usage guidelines

The Burst feature is especially useful for reducing packet losses under the following circumstances:

·     Traffic enters a device from a high-speed interface and goes out of a low-speed interface.

·     Traffic enters a device from multiple same-rate interfaces and goes out of an interface with the same rate.

The Burst feature takes effect only on known unicast packets.

Examples

# Enable the Burst feature.

<Sysname> system-view

[Sysname] burst-mode enable

display buffer

Use display buffer to display buffer size settings.

Syntax

display buffer [ slot slot-number ] [ queue [ queue-id ] ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

slot slot-number: Specifies an IRF member device by its member ID (slot number). If you do not specify an IRF member device, this command displays buffer size settings for all IRF member devices.

queue queue-id: Specifies a queue by its ID in the range of 0 to 7.

Usage guidelines

If you do not specify the queue keyword, this command displays the total shared-area ratio.

If you specify the queue keyword, this command displays the fixed-area ratio and shared-area ratio for all queues.

If you specify a queue, this command displays the fixed-area size and shared-area size for the specified queue.

Examples

# Display the total shared-area ratio.

<Sysname> display buffer

Slot  Type    Eg(Total-shared)                                                 

1     cell    25                                                               

                                                                               

          Eg: Size of the sending buffer                                       

Total-shared: Size of the shared buffer for all ports                          

        Unit: Ratio

# Display the fixed-area ratio and shared-area ratio for each queue.

<Sysname> display buffer queue

Slot  Queue        Type    Eg(Guaranteed , Shared)                             

2     0            cell    20 , 33                                             

2     1            cell    14 , 33                                             

2     2-7          cell    11 , 33                                             

                                                                               

          Eg: Size of the sending buffer                                       

  Guaranteed: Size of the minimum guaranteed buffer per queue                  

      Shared: Size of the maximum shared buffer per queue                      

        Unit: Ratio

Table 2 Command output

Field	Description
Slot	ID of an IRF member device.
Type	Resource type. The device supports only cell resources.
Queue	Queue ID in the range of 0 to 7.
Eg	Egress buffer.
(Total-shared)	Total shared-area size.
(Guaranteed , Shared)	·     Guaranteed—Fixed-area ratio for a queue. ·     Shared—Shared-area ratio for a queue. The default fixed-area ratio for a queue is 12.5%, but the default value in the display buffer queue command output is 12%.
Unit	Unit for configuring the data buffer. The device supports only ratio.

 

display buffer usage

Use display buffer usage to display buffer usage.

Syntax

display buffer usage [ slot slot-number ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

slot slot-number: Specifies an IRF member device by its member ID (slot number). If you do not specify an IRF member device, this command displays buffer usage for all IRF member devices.

Examples

# Display data buffer usage.

<Sysname> display buffer usage

Egress total-shared cell buffer usage on slot 1

Total:    3872 KB                                                               

Used:       0 KB                                                               

Free:    3872 KB                                                               

                              5sec    1min    5min                             

------------------------------------------------------------------             

Block 1                         0%      0%      0%                             

GigabitEthernet1/0/1            0%      0%      0%                              

GigabitEthernet1/0/2            0%      0%      0%                             

GigabitEthernet1/0/3            0%      0%      0%                             

GigabitEthernet1/0/4            0%      0%      0%                              

GigabitEthernet1/0/5            0%      0%      0%                             

GigabitEthernet1/0/6            0%      0%      0%                             

GigabitEthernet1/0/7            0%      0%      0%                             

GigabitEthernet1/0/8            0%      0%      0%                             

GigabitEthernet1/0/9            0%      0%      0%                             

GigabitEthernet1/0/10           0%      0%      0%                             

GigabitEthernet1/0/11           0%      0%      0%                             

GigabitEthernet1/0/12           0%      0%      0%                             

GigabitEthernet1/0/13           0%      0%      0%                             

GigabitEthernet1/0/14           0%      0%      0%                             

GigabitEthernet1/0/15           0%      0%      0%                             

GigabitEthernet1/0/16           0%      0%      0%                             

GigabitEthernet1/0/17           0%      0%      0%                             

GigabitEthernet1/0/18           0%      0%      0%                             

GigabitEthernet1/0/19           0%      0%      0%                             

GigabitEthernet1/0/20           0%      0%      0%                             

GigabitEthernet1/0/21           0%      0%      0%                             

GigabitEthernet1/0/22           0%      0%      0%                             

GigabitEthernet1/0/23           0%      0%      0%                             

GigabitEthernet1/0/24           0%      0%      0%                             

GigabitEthernet1/0/25           0%      0%      0%                             

GigabitEthernet1/0/26           0%      0%      0%                              

GigabitEthernet1/0/27           0%      0%      0%                             

GigabitEthernet1/0/28           0%      0%      0%                             

GigabitEthernet1/0/29           0%      0%      0%                              

GigabitEthernet1/0/30           0%      0%      0%                             

GigabitEthernet1/0/31           0%      0%      0%                             

GigabitEthernet1/0/32           0%      0%      0%                              

GigabitEthernet1/0/33           0%      0%      0%                             

GigabitEthernet1/0/34           0%      0%      0%                             

GigabitEthernet1/0/35           0%      0%      0%                             

GigabitEthernet1/0/36           0%      0%      0%                             

GigabitEthernet1/0/37           0%      0%      0%                             

GigabitEthernet1/0/38           0%      0%      0%                             

GigabitEthernet1/0/39           0%      0%      0%                             

GigabitEthernet1/0/40           0%      0%      0%                             

GigabitEthernet1/0/41           0%      0%      0%                             

GigabitEthernet1/0/42           0%      0%      0%                             

GigabitEthernet1/0/43           0%      0%      0%                             

GigabitEthernet1/0/44           0%      0%      0%                             

GigabitEthernet1/0/45           0%      0%      0%                             

GigabitEthernet1/0/46           0%      0%      0%                             

GigabitEthernet1/0/47           0%      0%      0%                             

GigabitEthernet1/0/48           0%      0%      0%                             

Ten-GigabitEthernet1/0/49       0%      0%      0%                             

Ten-GigabitEthernet1/0/50       0%      0%      0%                             

Ten-GigabitEthernet1/0/51       0%      0%      0%                             

Ten-GigabitEthernet1/0/52       0%      0%      0%

Table 3 Command output

Field	Description
Egress total-shared cell buffer usage on slot	Usage of the shared area of cell resources on an IRF member device.
Total	Total size of the data buffer.
Used	Size of used data buffer.
Free	Size of free data buffer.
Block 1	Block where the port resides. The block where the ports on the front panel of the device reside is fixed to Block 1.
5sec	Percentage of the buffer that the port uses for the last 5 seconds.
1min	Percentage of the buffer that the port uses for the last 1 minute.
5min	Percentage of the buffer that the port uses for the last 5 minutes.