diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/DocBook/usb.tmpl | 1 | ||||
| -rw-r--r-- | Documentation/cpu-freq/governors.txt | 62 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 23 |
3 files changed, 83 insertions, 3 deletions
diff --git a/Documentation/DocBook/usb.tmpl b/Documentation/DocBook/usb.tmpl index 15ce0f21e5e0..320af25de3a2 100644 --- a/Documentation/DocBook/usb.tmpl +++ b/Documentation/DocBook/usb.tmpl @@ -253,6 +253,7 @@ !Edrivers/usb/core/urb.c !Edrivers/usb/core/message.c !Edrivers/usb/core/file.c +!Edrivers/usb/core/driver.c !Edrivers/usb/core/usb.c !Edrivers/usb/core/hub.c </chapter> diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index 933fae74c337..f4b8dc4237e6 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -27,6 +27,7 @@ Contents: 2.2 Powersave 2.3 Userspace 2.4 Ondemand +2.5 Conservative 3. The Governor Interface in the CPUfreq Core @@ -110,9 +111,64 @@ directory. The CPUfreq govenor "ondemand" sets the CPU depending on the current usage. To do this the CPU must have the capability to -switch the frequency very fast. - - +switch the frequency very quickly. There are a number of sysfs file +accessible parameters: + +sampling_rate: measured in uS (10^-6 seconds), this is how often you +want the kernel to look at the CPU usage and to make decisions on +what to do about the frequency. Typically this is set to values of +around '10000' or more. + +show_sampling_rate_(min|max): the minimum and maximum sampling rates +available that you may set 'sampling_rate' to. + +up_threshold: defines what the average CPU usaged between the samplings +of 'sampling_rate' needs to be for the kernel to make a decision on +whether it should increase the frequency. For example when it is set +to its default value of '80' it means that between the checking +intervals the CPU needs to be on average more than 80% in use to then +decide that the CPU frequency needs to be increased. + +sampling_down_factor: this parameter controls the rate that the CPU +makes a decision on when to decrease the frequency. When set to its +default value of '5' it means that at 1/5 the sampling_rate the kernel +makes a decision to lower the frequency. Five "lower rate" decisions +have to be made in a row before the CPU frequency is actually lower. +If set to '1' then the frequency decreases as quickly as it increases, +if set to '2' it decreases at half the rate of the increase. + +ignore_nice_load: this parameter takes a value of '0' or '1', when set +to '0' (its default) then all processes are counted towards towards the +'cpu utilisation' value. When set to '1' then processes that are +run with a 'nice' value will not count (and thus be ignored) in the +overal usage calculation. This is useful if you are running a CPU +intensive calculation on your laptop that you do not care how long it +takes to complete as you can 'nice' it and prevent it from taking part +in the deciding process of whether to increase your CPU frequency. + + +2.5 Conservative +---------------- + +The CPUfreq governor "conservative", much like the "ondemand" +governor, sets the CPU depending on the current usage. It differs in +behaviour in that it gracefully increases and decreases the CPU speed +rather than jumping to max speed the moment there is any load on the +CPU. This behaviour more suitable in a battery powered environment. +The governor is tweaked in the same manner as the "ondemand" governor +through sysfs with the addition of: + +freq_step: this describes what percentage steps the cpu freq should be +increased and decreased smoothly by. By default the cpu frequency will +increase in 5% chunks of your maximum cpu frequency. You can change this +value to anywhere between 0 and 100 where '0' will effectively lock your +CPU at a speed regardless of its load whilst '100' will, in theory, make +it behave identically to the "ondemand" governor. + +down_threshold: same as the 'up_threshold' found for the "ondemand" +governor but for the opposite direction. For example when set to its +default value of '20' it means that if the CPU usage needs to be below +20% between samples to have the frequency decreased. 3. The Governor Interface in the CPUfreq Core ============================================= diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index ebc09a159f62..2b7cf19a06ad 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -46,6 +46,29 @@ ipfrag_secret_interval - INTEGER for the hash secret) for IP fragments. Default: 600 +ipfrag_max_dist - INTEGER + ipfrag_max_dist is a non-negative integer value which defines the + maximum "disorder" which is allowed among fragments which share a + common IP source address. Note that reordering of packets is + not unusual, but if a large number of fragments arrive from a source + IP address while a particular fragment queue remains incomplete, it + probably indicates that one or more fragments belonging to that queue + have been lost. When ipfrag_max_dist is positive, an additional check + is done on fragments before they are added to a reassembly queue - if + ipfrag_max_dist (or more) fragments have arrived from a particular IP + address between additions to any IP fragment queue using that source + address, it's presumed that one or more fragments in the queue are + lost. The existing fragment queue will be dropped, and a new one + started. An ipfrag_max_dist value of zero disables this check. + + Using a very small value, e.g. 1 or 2, for ipfrag_max_dist can + result in unnecessarily dropping fragment queues when normal + reordering of packets occurs, which could lead to poor application + performance. Using a very large value, e.g. 50000, increases the + likelihood of incorrectly reassembling IP fragments that originate + from different IP datagrams, which could result in data corruption. + Default: 64 + INET peer storage: inet_peer_threshold - INTEGER |