A little more detail:

• It appears to me that the ODL OVSDB subsystem sends an initial query to the switch when an OVSDB connection comes up
• If the response to this query is 'too large' (current 100,000 bytes), ODL closes the connection.
• If the switch is configured to open the OVSDB connection, this process repeats indefinitely and the OVSDB subsystem isn't usable (at least for that switch)

A lot of detail:

Running code that I built myself from the stable/helium branch (more or less at stable helium 2).

I had one switch in my system with A LOT of ovsdb rows and I hit this problem

• My switch is configured to connect to my controller when the controller starts up.
• My controller starts and the switch connects
• The OVSDB subsystem begins pulling information from my switch
• My controller closes the OVSDB connection
• My switch attempts to reconnect
• repeat forever

I eventually was able to set a break point and get a stack trace. The problem is in
ovsdb/library/src/main/java/org/opendaylight/ovsdb/lib/jsonrpc/JsonRpcDecoder.java around line 116 (in the decode(ChannelHandlerContext ctx, ByteBuf buf, List<Object> out) method)

for (; i < buf.writerIndex(); i++) {
switch (buf.getByte) {
case '

{': if (!inS) leftCurlies++; break; case '}

':
if (!inS) rightCurlies++;
break;
case '"':

{ if (buf.getByte(i - 1) != '\\') inS = !inS; break; }

}

if (leftCurlies != 0 && leftCurlies == rightCurlies && !inS)

{ ByteBuf slice = buf.readSlice(1 + i - buf.readerIndex()); JsonParser jp = jacksonJsonFactory.createParser(new ByteBufInputStream(slice)); JsonNode root = jp.readValueAsTree(); out.add(root); leftCurlies = rightCurlies = lastRecordBytes = 0; recordsRead++; break; }

if (i - buf.readerIndex() >= maxFrameLength)

{ fail(ctx, i - buf.readerIndex()); }

...

private void fail(ChannelHandlerContext ctx, long frameLength) {
logger.error("JSON too big. JSON content exceeded limit of {} bytes", maxFrameLength);
if (frameLength > 0)

{ ctx.fireExceptionCaught( new TooLongFrameException( "frame length exceeds " + maxFrameLength + ": " + frameLength + " - discarded")); }

else

{ ctx.fireExceptionCaught( new TooLongFrameException( "frame length exceeds " + maxFrameLength + " - discarding")); }

}