Merge #17469: test: Remove fragile assert_memory_usage_stable

fac942ca57dce6cfa5655a3ac8664d6a051bc01f test: Remove fragile assert_memory_usage_stable (MarcoFalke)

Pull request description:

  This test fails on arm64 and a fuzz tests seems inappropriate for the functional test suite anyway, so remove it.

  Example failures:

  * https://travis-ci.org/bitcoin/bitcoin/jobs/611497963#L14517
  * https://travis-ci.org/MarcoFalke/bitcoin-core/jobs/611029104#L3876

ACKs for top commit:
  jamesob:
    ACK fac942ca57

Tree-SHA512: 3577e7ce5891d221cb798454589ba796ed0c06621a26351bb919c23bc6bb46aafcd0b11cb02bbfde64b74d67cb2950da44959a7ecdc436491a34e8b045c1ccf4

test/functional/p2p_invalid_messages.py

@@ -4,7 +4,6 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test node responses to invalid network messages."""
 import asyncio
-import os
 import struct
 import sys
 
@@ -66,13 +65,7 @@ class InvalidMessagesTest(BitcoinTestFramework):
         msg_at_size = msg_unrecognized(str_data="b" * valid_data_limit)
         assert len(msg_at_size.serialize()) == msg_limit
 
-        increase_allowed = 0.5
+        self.log.info("Sending a bunch of large, junk messages to test memory exhaustion. May take a bit...")
-        if [s for s in os.environ.get("BITCOIN_CONFIG", "").split(" ") if "--with-sanitizers" in s and "address" in s]:
-            increase_allowed = 3.5
-        with node.assert_memory_usage_stable(increase_allowed=increase_allowed):
-            self.log.info(
-                "Sending a bunch of large, junk messages to test "
-                "memory exhaustion. May take a bit...")
 
         # Run a bunch of times to test for memory exhaustion.
         for _ in range(80):

test/functional/test_framework/test_node.py

@@ -148,28 +148,6 @@ class TestNode():
         ]
         return PRIV_KEYS[self.index]
 
-    def get_mem_rss_kilobytes(self):
-        """Get the memory usage (RSS) per `ps`.
-
-        If process is stopped or `ps` is unavailable, return None.
-        """
-        if not (self.running and self.process):
-            self.log.warning("Couldn't get memory usage; process isn't running.")
-            return None
-
-        try:
-            return int(subprocess.check_output(
-                "ps h -o rss {}".format(self.process.pid),
-                shell=True, stderr=subprocess.DEVNULL).strip())
-
-        # Catching `Exception` broadly to avoid failing on platforms where ps
-        # isn't installed or doesn't work as expected, e.g. OpenBSD.
-        #
-        # We could later use something like `psutils` to work across platforms.
-        except Exception:
-            self.log.exception("Unable to get memory usage")
-            return None
-
     def _node_msg(self, msg: str) -> str:
         """Return a modified msg that identifies this node by its index as a debugging aid."""
         return "[node %d] %s" % (self.index, msg)
@@ -358,33 +336,6 @@ class TestNode():
             time.sleep(0.05)
         self._raise_assertion_error('Expected messages "{}" does not partially match log:\n\n{}\n\n'.format(str(expected_msgs), print_log))
 
-    @contextlib.contextmanager
-    def assert_memory_usage_stable(self, *, increase_allowed=0.03):
-        """Context manager that allows the user to assert that a node's memory usage (RSS)
-        hasn't increased beyond some threshold percentage.
-
-        Args:
-            increase_allowed (float): the fractional increase in memory allowed until failure;
-                e.g. `0.12` for up to 12% increase allowed.
-        """
-        before_memory_usage = self.get_mem_rss_kilobytes()
-
-        yield
-
-        after_memory_usage = self.get_mem_rss_kilobytes()
-
-        if not (before_memory_usage and after_memory_usage):
-            self.log.warning("Unable to detect memory usage (RSS) - skipping memory check.")
-            return
-
-        perc_increase_memory_usage = 1 - (float(before_memory_usage) / after_memory_usage)
-
-        if perc_increase_memory_usage > increase_allowed:
-            self._raise_assertion_error(
-                "Memory usage increased over threshold of {:.3f}% from {} to {} ({:.3f}%)".format(
-                    increase_allowed * 100, before_memory_usage, after_memory_usage,
-                    perc_increase_memory_usage * 100))
-
     @contextlib.contextmanager
     def profile_with_perf(self, profile_name):
         """