Reserve max buffer size in delta performer.
From the analysis in b/34220646#comment68, repeatedly insertion to the
vector caused memory reallocation and potentially increase the peak
memory usage a lot. This issue can be easily fixed by reserving the
memory first since we know the patch size in advance.
Bug: 34220646
Test: run an incremental update on sailfish and check the memory usage.
Change-Id: I89726cc5c8d51c2e43ac8616c711eeabc3f88dbc
diff --git a/payload_consumer/delta_performer.cc b/payload_consumer/delta_performer.cc
index d384e45..4ac0c49 100644
--- a/payload_consumer/delta_performer.cc
+++ b/payload_consumer/delta_performer.cc
@@ -273,6 +273,7 @@
size_t read_len = min(count, max - buffer_.size());
const char* bytes_start = *bytes_p;
const char* bytes_end = bytes_start + read_len;
+ buffer_.reserve(max);
buffer_.insert(buffer_.end(), bytes_start, bytes_end);
*bytes_p = bytes_end;
*count_p = count - read_len;