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authorSteven Rostedt <rostedt@goodmis.org>2008-11-12 17:52:36 -0500
committerIngo Molnar <mingo@elte.hu>2008-11-13 09:49:21 +0100
commita94c80e78bc9f4493ffc25a02d5d7bcd93c399d0 (patch)
tree7bccb9ade6edc033887db7c6f9f7157c5d612e3c /Documentation/ftrace.txt
parent24de38620dd3504782c90c0892eef888d0c351e9 (diff)
ftrace: rename trace_entries to buffer_size_kb
Impact: rename of debugfs file trace_entries to buffer_size_kb The original ftrace had fixed size entries, and the number of entries was shown and modified via the file called trace_entries. By converting to the unified trace buffer, we now allow for variable size entries which makes the meaning of trace_entries pointless. Since trace_size might be confused to the size of the trace, this patch names it "buffer_size_kb" (thanks to Arjan van de Ven for this idea). [ mingo@elte.hu: changed from buffer_size to buffer_size_kb ] ( Note, the units are still bytes - the next patch changes that, to keep the wide rename patch separate from the unit-change patch. ) Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'Documentation/ftrace.txt')
-rw-r--r--Documentation/ftrace.txt18
1 files changed, 9 insertions, 9 deletions
diff --git a/Documentation/ftrace.txt b/Documentation/ftrace.txt
index 9cc4d685dde5..a1b58777839b 100644
--- a/Documentation/ftrace.txt
+++ b/Documentation/ftrace.txt
@@ -94,7 +94,7 @@ of ftrace. Here is a list of some of the key files:
only be recorded if the latency is greater than
the value in this file. (in microseconds)
- trace_entries: This sets or displays the number of bytes each CPU
+ buffer_size_kb: This sets or displays the number of bytes each CPU
buffer can hold. The tracer buffers are the same size
for each CPU. The displayed number is the size of the
CPU buffer and not total size of all buffers. The
@@ -1299,13 +1299,13 @@ trace entries
-------------
Having too much or not enough data can be troublesome in diagnosing
-an issue in the kernel. The file trace_entries is used to modify
+an issue in the kernel. The file buffer_size_kb is used to modify
the size of the internal trace buffers. The number listed
is the number of entries that can be recorded per CPU. To know
the full size, multiply the number of possible CPUS with the
number of entries.
- # cat /debug/tracing/trace_entries
+ # cat /debug/tracing/buffer_size_kb
65620
Note, to modify this, you must have tracing completely disabled. To do that,
@@ -1313,8 +1313,8 @@ echo "nop" into the current_tracer. If the current_tracer is not set
to "nop", an EINVAL error will be returned.
# echo nop > /debug/tracing/current_tracer
- # echo 100000 > /debug/tracing/trace_entries
- # cat /debug/tracing/trace_entries
+ # echo 100000 > /debug/tracing/buffer_size_kb
+ # cat /debug/tracing/buffer_size_kb
100045
@@ -1323,8 +1323,8 @@ are held in individual pages. It allocates the number of pages it takes
to fulfill the request. If more entries may fit on the last page
then they will be added.
- # echo 1 > /debug/tracing/trace_entries
- # cat /debug/tracing/trace_entries
+ # echo 1 > /debug/tracing/buffer_size_kb
+ # cat /debug/tracing/buffer_size_kb
85
This shows us that 85 entries can fit in a single page.
@@ -1332,8 +1332,8 @@ This shows us that 85 entries can fit in a single page.
The number of pages which will be allocated is limited to a percentage
of available memory. Allocating too much will produce an error.
- # echo 1000000000000 > /debug/tracing/trace_entries
+ # echo 1000000000000 > /debug/tracing/buffer_size_kb
-bash: echo: write error: Cannot allocate memory
- # cat /debug/tracing/trace_entries
+ # cat /debug/tracing/buffer_size_kb
85