logd: document ro.logd.size
Bad comment advise in LogBuffer.cpp results in partners failing to
considering using ro.logd.size to set the platform buffer size
default.
NB: It is not good practice to increase the log buffer size to deal
with logspam, as increases will result in logd scale issues getting
closer to hitting the background cgroup cpu cap. Once we hit that
cap, logd spirals, pruning old entries slower than the incoming log
entries. logd.writer will take 100% cpu.
Change-Id: If4a7a74f300d078eeaed0ffd3eb3fd77d1f9fe90
diff --git a/logd/README.property b/logd/README.property
index 75d9eb0..22f86b9 100644
--- a/logd/README.property
+++ b/logd/README.property
@@ -15,7 +15,11 @@
persist.logd.size number ro Global default size of the buffer for
all log ids at initial startup, at
runtime use: logcat -b all -G <value>
-ro.logd.size number svelte default for persist.logd.size
+ro.logd.size number svelte default for persist.logd.size. Larger
+ platform default sizes than 256KB are
+ known to not scale well under log spam
+ pressure. Address the spam first,
+ resist increasing the log buffer.
persist.logd.size.<buffer> number ro Size of the buffer for <buffer> log
ro.logd.size.<buffer> number svelte default for persist.logd.size.<buffer>
ro.config.low_ram bool false if true, logd.statistics, logd.kernel