[PATCH 0/2] Reclaim memory & serialize access

[Tony Asleson]

Changes to prevent memory from leaking and allow multiple
clients to operate, although their access is serialized.

These are updated changes from suggestions from Andy.

Tony Asleson (2):
  Re-claim memory in C library periodically
  Serialize service processing.

 targetd/block.py | 11 +++++++++++
 targetd/main.py  | 10 +++++-----
 2 files changed, 16 insertions(+), 5 deletions(-)

-- 
1.8.2.1

[PATCH 1/2] Re-claim memory in C library periodically

[Tony Asleson]

The lvm C library requires that you close/re-open for long
running processes to reclaim memory.

Signed-off-by: Tony Asleson <tasleson(a)redhat.com&gt;
---
 targetd/block.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/targetd/block.py b/targetd/block.py
index da78872..35c27ab 100644
--- a/targetd/block.py
+++ b/targetd/block.py
@@ -54,13 +54,24 @@ def vgopen(pool_name):
     """
     Helper function to check/close vg for us.
     """
+    global lib_calls
     pool_check(pool_name)
     with contextlib.closing(lvm.vgOpen(pool_name, "w")) as vg:
         yield vg
 
+    #Clean library periodically
+    lib_calls += 1
+    if lib_calls > 50:
+        try:
+            #May not be present if using older library
+            lvm.gc()
+        except AttributeError:
+            pass
+        lib_calls = 0
 
 pools = []
 target_name = None
+lib_calls = 0
 
 
 #
-- 
1.8.2.1

[PATCH 2/2] Serialize service processing.

[Tony Asleson]

There are a number of things that targetd is calling that cannot
be executed concurrently.  Make the service only handle one
request at a time.

Signed-off-by: Tony Asleson <tasleson(a)redhat.com&gt;
---
 targetd/main.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/targetd/main.py b/targetd/main.py
index 69ffa22..8db95d7 100644
--- a/targetd/main.py
+++ b/targetd/main.py
@@ -213,11 +213,11 @@ class TargetHandler(BaseHTTPRequestHandler):
                 self.wfile.write(rpcdata)
 
 
-class ThreadedHTTPServer(ThreadingMixIn, HTTPServer, object):
-    """Handle requests in a separate thread."""
+class HTTPService(HTTPServer, object):
+    """Handle requests one at a time"""
 
 
-class TLSThreadedHTTPServer(ThreadedHTTPServer):
+class TLSHTTPService(HTTPService):
     """Also use TLS to encrypt the connection"""
 
     def finish_request(self, sock, addr):
@@ -288,10 +288,10 @@ def main():
     update_mapping()
 
     if config['ssl']:
-        server_class = TLSThreadedHTTPServer
+        server_class = TLSHTTPService
         note = "(TLS yes)"
     else:
-        server_class = ThreadedHTTPServer
+        server_class = HTTPService
         note = "(TLS no)"
 
     try:
-- 
1.8.2.1

[Andy Grover]

On 07/19/2013 10:22 AM, Tony Asleson wrote:
>  Changes to prevent memory from leaking and allow multiple
>  clients to operate, although their access is serialized.
>
>  These are updated changes from suggestions from Andy.
>
>  Tony Asleson (2):
>     Re-claim memory in C library periodically
>     Serialize service processing.
>
>    targetd/block.py | 11 +++++++++++
>    targetd/main.py  | 10 +++++-----
>    2 files changed, 16 insertions(+), 5 deletions(-)
>  
Thanks Tony.

Two incredibly small notes. Please put a space after the '#'s in the 
comments in patch 1. In patch 2, please make note of why we're going 
back to single-threaded server (i.e. b/c liblvm requires it), either in 
a comment or the HTTPService docstring.

Otherwise looks great, please commit, and thanks also for the testing 
you did on these.

Regards -- Andy