* Adding request time limiting strategy for texture requests, though this isn't useable yet

0.6.0-stable
Justin Clarke Casey 2008-04-03 15:28:50 +00:00
parent 6ef4f1bdae
commit 5fe4a39927
3 changed files with 153 additions and 5 deletions

View File

@ -80,7 +80,7 @@ namespace OpenSim.Framework.Communications.Limit
/// </summary>
public bool IsFirstRefusal(TId id)
{
if (m_maxRequests + 1 == requestCounts[id])
if (requestCounts.ContainsKey(id) && m_maxRequests + 1 == requestCounts[id])
{
return true;
}

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@ -0,0 +1,140 @@
/*
* Copyright (c) Contributors, http://opensimulator.org/
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the OpenSim Project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Collections.Generic;
namespace OpenSim.Framework.Communications.Limit
{
/// <summary>
/// Limit requests by discarding repeat attempts that occur within a given time period
///
/// XXX Don't use this for limiting texture downloading, at least not until we better handle multiple requests
/// for the same texture at different resolutions.
/// </summary>
public class TimeLimitStrategy<TId> : IRequestLimitStrategy<TId>
{
/// <summary>
/// Record the time at which an asset request occurs.
/// </summary>
private readonly Dictionary<TId, Request> requests = new Dictionary<TId, Request>();
/// <summary>
/// The minimum time period between which requests for the same data will be serviced.
/// </summary>
private readonly TimeSpan m_repeatPeriod;
public TimeSpan RepeatPeriod
{
get { return m_repeatPeriod; }
}
/// <summary></summary>
/// <param name="repeatPeriod"></param>
public TimeLimitStrategy(TimeSpan repeatPeriod)
{
m_repeatPeriod = repeatPeriod;
}
/// <summary>
/// <see cref="IRequestLimitStrategy"/>
/// </summary>
public bool AllowRequest(TId id)
{
if (IsMonitoringRequests(id))
{
DateTime now = DateTime.Now;
TimeSpan elapsed = now - requests[id].Time;
if (elapsed < RepeatPeriod)
{
requests[id].Refusals += 1;
return false;
}
requests[id].Time = now;
}
return true;
}
/// <summary>
/// <see cref="IRequestLimitStrategy"/>
/// </summary>
public bool IsFirstRefusal(TId id)
{
if (IsMonitoringRequests(id))
{
if (1 == requests[id].Refusals)
{
return true;
}
}
return false;
}
/// <summary>
/// <see cref="IRequestLimitStrategy"/>
/// </summary>
public void MonitorRequests(TId id)
{
if (!IsMonitoringRequests(id))
{
requests.Add(id, new Request(System.DateTime.Now));
}
}
/// <summary>
/// <see cref="IRequestLimitStrategy"/>
/// </summary>
public bool IsMonitoringRequests(TId id)
{
return requests.ContainsKey(id);
}
}
/// <summary>
/// Private request details.
/// </summary>
class Request
{
/// <summary>
/// Time of last request
/// </summary>
public DateTime Time;
/// <summary>
/// Number of refusals associated with this request
/// </summary>
public int Refusals;
public Request(DateTime time)
{
Time = time;
}
}
}

View File

@ -50,12 +50,16 @@ namespace OpenSim.Region.Environment.Modules
= log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
/// <summary>
/// We will allow the client to request the same texture n times before dropping further requests
/// We will allow the client to request the same missing texture n times before dropping further requests
///
/// This number includes repeated requests for the same texture at different resolutions (which we don't
/// currently handle properly as far as I know). However, this situation should be handled in a more
/// sophisticated way.
/// </summary>
private static readonly int MAX_ALLOWED_TEXTURE_REQUESTS = 5;
/// <summary>
/// We're going to limit repeated requests for the same missing texture.
/// We're going to limit requests for the same missing texture.
/// XXX This is really a temporary solution to deal with the situation where a client continually requests
/// the same missing textures
/// </summary>
@ -63,7 +67,7 @@ namespace OpenSim.Region.Environment.Modules
= new RepeatLimitStrategy<LLUUID>(MAX_ALLOWED_TEXTURE_REQUESTS);
/// <summary>
/// XXX Also going to limit repeated requests for found textures.
/// XXX Also going to limit requests for found textures.
/// </summary>
private readonly IRequestLimitStrategy<LLUUID> foundTextureLimitStrategy
= new RepeatLimitStrategy<LLUUID>(MAX_ALLOWED_TEXTURE_REQUESTS);
@ -115,6 +119,10 @@ namespace OpenSim.Region.Environment.Modules
{
if (!foundTextureLimitStrategy.AllowRequest(e.RequestedAssetID))
{
// m_log.DebugFormat(
// "[USER TEXTURE DOWNLOAD SERVICE]: Refusing request for {0} from client {1}",
// e.RequestedAssetID, m_client.AgentId);
return;
}
else if (!missingTextureLimitStrategy.AllowRequest(e.RequestedAssetID))