From 7ab6c710c047a411797cc9fc7790930cf91d95d2 Mon Sep 17 00:00:00 2001 From: Pasquale Imputato Date: Sat, 24 Sep 2016 15:36:10 +0200 Subject: [PATCH] network: Set a proper default value for BQL HoldTime attribute --- src/network/doc/queue-limits.rst | 10 +++++----- src/network/utils/dynamic-queue-limits.cc | 2 +- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/src/network/doc/queue-limits.rst b/src/network/doc/queue-limits.rst index 4285a04da..c57d2c71a 100644 --- a/src/network/doc/queue-limits.rst +++ b/src/network/doc/queue-limits.rst @@ -64,11 +64,11 @@ Three attributes are defined in the DynamicQueueLimits class: * ``MaxLimit``: Maximum limit * ``MinLimit``: Minimum limit -The HoldTime attribute is set to 1/HZ by the Linux DQL library. The default value -is 4 ms. Typical values for HoldTime ranges from 10 to 1 ms (corresponding to the typical -values of HZ which varies from 100 to 1000). Reducing the HoldTime increases the responsiveness of -DQL with consequent greater number of limit variation events. The limit calculated from DQL is in the -range from MinLimit to MaxLimit. The default values are respectively 0 and DQL_MAX_LIMIT. +The DQL algorithm hold time is 1 s. Reducing the HoldTime increases the responsiveness of +DQL with consequent greater number of limit variation events. Conversely, increasing the HoldTime +decreases the responsiveness of DQL with a minor number of limit variation events. +The limit calculated by DQL is in the range from MinLimit to MaxLimit. +The default values are respectively 0 and DQL_MAX_LIMIT. Increasing the MinLimit is recommended in case of higher NetDevice transmission rate (e.g. 1 Gbps) while reducing the MaxLimit is recommended in case of lower NetDevice transmission rate (e.g. 500 Kbps). diff --git a/src/network/utils/dynamic-queue-limits.cc b/src/network/utils/dynamic-queue-limits.cc index ed3be5cb4..ad46a3429 100644 --- a/src/network/utils/dynamic-queue-limits.cc +++ b/src/network/utils/dynamic-queue-limits.cc @@ -50,7 +50,7 @@ DynamicQueueLimits::GetTypeId (void) .AddConstructor () .AddAttribute ("HoldTime", "The DQL algorithm hold time", - StringValue ("4ms"), // 1/HZ + StringValue ("1s"), MakeTimeAccessor (&DynamicQueueLimits::m_slackHoldTime), MakeTimeChecker ()) .AddAttribute ("MaxLimit",