Bug 1253452
| Summary: | Errors on "Reducing the TCP Delayed Ack Timeout" doc | ||
|---|---|---|---|
| Product: | Red Hat Enterprise MRG | Reporter: | Daniel Bristot de Oliveira <daolivei> |
| Component: | Realtime_Tuning_Guide | Assignee: | Scott Mumford <smumford> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | MRG Quality Engineering <mrgqe-bugs> |
| Severity: | medium | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 2.5 | CC: | bhu, lgoncalv, msvistun, tcapek, williams |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2015-11-12 01:07:48 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Description of problem: There are two errors at the following chapter/section [1]: 2. General System Tuning 2.13. Reducing the TCP delayed ack timeout at the following statements: 1) "This value defaults to 40ms." This is the default value on non-rt kernel. On rt kernel it is 4ms. 2) "Write the desired minimum value, in microseconds, to /proc/sys/net/ipv4/tcp_delack_min:" The correct unit of time is milliseconds, and not microseconds. Moreover, the patch that implements this feature [2] also includes the tcp_ato_min knob, but I did not find the documentation for it. [1] https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_MRG/2/html/Realtime_Tuning_Guide/sect-Realtime_Tuning_Guide-General_System_Tuning-Reducing_the_TCP_delayed_ack_timeout.html [2] kernel-rt specific commit: c00451d MRG: RFC: Nagle latency tuning [ this bug is the same report of BZ1253448 ]