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diff --git a/linden/indra/llmessage/llthrottle.cpp b/linden/indra/llmessage/llthrottle.cpp
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+++ b/linden/indra/llmessage/llthrottle.cpp
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+/** 
+ * @file llthrottle.cpp
+ * @brief LLThrottle class used for network bandwidth control.
+ *
+ * Copyright (c) 2001-2007, Linden Research, Inc.
+ * 
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlife.com/developers/opensource/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at http://secondlife.com/developers/opensource/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ */
+
+#include "linden_common.h"
+
+#include "llthrottle.h"
+#include "llmath.h"
+#include "lldatapacker.h"
+#include "message.h"
+
+
+LLThrottle::LLThrottle(const F32 rate)
+{
+        mRate = rate;
+        mAvailable = 0.f;
+        mLookaheadSecs = 0.25f;
+        mLastSendTime = LLMessageSystem::getMessageTimeSeconds(TRUE);
+}
+
+
+void LLThrottle::setRate(const F32 rate)
+{
+        // Need to accumulate available bits when adjusting the rate.
+        mAvailable = getAvailable();
+        mLastSendTime = LLMessageSystem::getMessageTimeSeconds();
+        mRate = rate;
+}
+
+F32 LLThrottle::getAvailable()
+{
+        // use a temporary bits_available
+        // since we don't want to change mBitsAvailable every time
+        F32 elapsed_time = (F32)(LLMessageSystem::getMessageTimeSeconds() - mLastSendTime);
+        return mAvailable + (mRate * elapsed_time);
+}
+
+BOOL LLThrottle::checkOverflow(const F32 amount)
+{
+        BOOL retval = TRUE;
+
+        F32 lookahead_amount = mRate * mLookaheadSecs;
+
+        // use a temporary bits_available
+        // since we don't want to change mBitsAvailable every time
+        F32 elapsed_time =  (F32)(LLMessageSystem::getMessageTimeSeconds() - mLastSendTime);
+        F32 amount_available = mAvailable + (mRate * elapsed_time);
+
+        if ((amount_available >= lookahead_amount) || (amount_available > amount))
+        {
+                // ...enough space to send this message
+                // Also do if > lookahead so we can use if amount > capped amount.
+                retval = FALSE;
+        }
+        
+        return retval;
+}
+
+BOOL LLThrottle::throttleOverflow(const F32 amount)
+{
+        F32 elapsed_time;
+        F32 lookahead_amount;
+        BOOL retval = TRUE;
+
+        lookahead_amount = mRate * mLookaheadSecs;
+
+        F64 mt_sec = LLMessageSystem::getMessageTimeSeconds();
+        elapsed_time = (F32)(mt_sec - mLastSendTime);
+        mLastSendTime = mt_sec;
+
+        mAvailable += mRate * elapsed_time;
+
+        if (mAvailable >= lookahead_amount)
+        {
+                // ...channel completely open, so allow send regardless
+                // of size.  This allows sends on very low BPS channels.
+                mAvailable = lookahead_amount;
+                retval = FALSE;
+        }
+        else if (mAvailable > amount)
+        {
+                // ...enough space to send this message
+                retval = FALSE;
+        }
+
+        // We actually already sent the bits.
+        mAvailable -= amount;
+
+        // What if bitsavailable goes negative?
+        // That's OK, because it means someone is banging on the channel,
+        // so we need some time to recover.
+
+        return retval;
+}
+
+
+
+const F32 THROTTLE_LOOKAHEAD_TIME = 1.f;        // seconds
+
+// Make sure that we don't set above these
+// values, even if the client asks to be set
+// higher
+// Note that these values are replicated on the 
+// client side to set max bandwidth throttling there,
+// in llviewerthrottle.cpp. These values are the sum
+// of the top two tiers of bandwidth there.
+
+F32 gThrottleMaximumBPS[TC_EOF] =
+{
+        150000.f, // TC_RESEND
+        170000.f, // TC_LAND
+        34000.f, // TC_WIND
+        34000.f, // TC_CLOUD
+        446000.f, // TC_TASK
+        446000.f, // TC_TEXTURE
+        220000.f, // TC_ASSET
+};
+
+// Start low until viewer informs us of capability
+// Asset and resend get high values, since they
+// aren't used JUST by the viewer necessarily.
+// This is a HACK and should be dealt with more properly on
+// circuit creation.
+
+F32 gThrottleDefaultBPS[TC_EOF] =
+{
+        100000.f, // TC_RESEND
+        4000.f, // TC_LAND
+        4000.f, // TC_WIND
+        4000.f, // TC_CLOUD
+        4000.f, // TC_TASK
+        4000.f, // TC_TEXTURE
+        100000.f, // TC_ASSET
+};
+
+// Don't throttle down lower than this
+// This potentially wastes 50 kbps, but usually
+// wont.
+F32 gThrottleMinimumBPS[TC_EOF] =
+{
+        10000.f,        // TC_RESEND
+        10000.f,        // TC_LAND
+         4000.f,        // TC_WIND
+         4000.f,        // TC_CLOUD
+        20000.f,        // TC_TASK
+        10000.f,        // TC_TEXTURE
+        10000.f,        // TC_ASSET
+};
+
+const char* THROTTLE_NAMES[TC_EOF] =
+{
+        "Resend ",
+        "Land   ",
+        "Wind   ",
+        "Cloud  ",
+        "Task   ",
+        "Texture",
+        "Asset  "
+};
+
+LLThrottleGroup::LLThrottleGroup()
+{
+        S32 i;
+        for (i = 0; i < TC_EOF; i++)
+        {
+                mThrottleTotal[i]       = gThrottleDefaultBPS[i];
+                mNominalBPS[i]          = gThrottleDefaultBPS[i];
+        }
+
+        resetDynamicAdjust();
+}
+
+void LLThrottleGroup::packThrottle(LLDataPacker &dp) const
+{
+        S32 i;
+        for (i = 0; i < TC_EOF; i++)
+        {
+                dp.packF32(mThrottleTotal[i], "Throttle");
+        }
+}
+
+void LLThrottleGroup::unpackThrottle(LLDataPacker &dp)
+{
+        S32 i;
+        for (i = 0; i < TC_EOF; i++)
+        {
+                F32 temp_throttle;
+                dp.unpackF32(temp_throttle, "Throttle");
+                temp_throttle = llclamp(temp_throttle, 0.f, 2250000.f);
+                mThrottleTotal[i] = temp_throttle;
+                if(mThrottleTotal[i] > gThrottleMaximumBPS[i])
+                {
+                        mThrottleTotal[i] = gThrottleMaximumBPS[i];
+                }
+        }
+}
+
+// Call this whenever mNominalBPS changes.  Need to reset
+// the measurement systems.  In the future, we should look
+// into NOT resetting the system.
+void LLThrottleGroup::resetDynamicAdjust()
+{
+        F64 mt_sec = LLMessageSystem::getMessageTimeSeconds();
+        S32 i;
+        for (i = 0; i < TC_EOF; i++)
+        {
+                mCurrentBPS[i]          = mNominalBPS[i];
+                mBitsAvailable[i]       = mNominalBPS[i] * THROTTLE_LOOKAHEAD_TIME;
+                mLastSendTime[i] = mt_sec;
+                mBitsSentThisPeriod[i] = 0;
+                mBitsSentHistory[i] = 0;
+        }
+        mDynamicAdjustTime = mt_sec;
+}
+
+
+BOOL LLThrottleGroup::setNominalBPS(F32* throttle_vec)
+{
+        BOOL changed = FALSE;
+        S32 i;
+        for (i = 0; i < TC_EOF; i++)
+        {
+                if (mNominalBPS[i] != throttle_vec[i])
+                {
+                        changed = TRUE;
+                        mNominalBPS[i] = throttle_vec[i];
+                }
+        }
+
+        // If we changed the nominal settings, reset the dynamic
+        // adjustment subsystem.
+        if (changed)
+        {
+                resetDynamicAdjust();
+        }
+
+        return changed;
+}
+
+
+BOOL LLThrottleGroup::checkOverflow(S32 throttle_cat, F32 bits)
+{
+        BOOL retval = TRUE;
+
+        F32 category_bps = mCurrentBPS[throttle_cat];
+        F32 lookahead_bits = category_bps * THROTTLE_LOOKAHEAD_TIME;
+
+        // use a temporary bits_available
+        // since we don't want to change mBitsAvailable every time
+        F32 elapsed_time = (F32)(LLMessageSystem::getMessageTimeSeconds() - mLastSendTime[throttle_cat]);
+        F32 bits_available = mBitsAvailable[throttle_cat] + (category_bps * elapsed_time);
+
+        if (bits_available >= lookahead_bits)
+        {
+                // ...channel completely open, so allow send regardless
+                // of size.  This allows sends on very low BPS channels.
+                mBitsAvailable[throttle_cat] = lookahead_bits;
+                retval = FALSE;
+        }
+        else if ( bits_available > bits )
+        {
+                // ...enough space to send this message
+                retval = FALSE;
+        }
+        
+        return retval;
+}
+
+BOOL LLThrottleGroup::throttleOverflow(S32 throttle_cat, F32 bits)
+{
+        F32 elapsed_time;
+        F32 category_bps;
+        F32 lookahead_bits;
+        BOOL retval = TRUE;
+
+        category_bps = mCurrentBPS[throttle_cat];
+        lookahead_bits = category_bps * THROTTLE_LOOKAHEAD_TIME;
+
+        F64 mt_sec = LLMessageSystem::getMessageTimeSeconds();
+        elapsed_time = (F32)(mt_sec - mLastSendTime[throttle_cat]);
+        mLastSendTime[throttle_cat] = mt_sec;
+        mBitsAvailable[throttle_cat] += category_bps * elapsed_time;
+
+        if (mBitsAvailable[throttle_cat] >= lookahead_bits)
+        {
+                // ...channel completely open, so allow send regardless
+                // of size.  This allows sends on very low BPS channels.
+                mBitsAvailable[throttle_cat] = lookahead_bits;
+                retval = FALSE;
+        }
+        else if ( mBitsAvailable[throttle_cat] > bits )
+        {
+                // ...enough space to send this message
+                retval = FALSE;
+        }
+
+        // We actually already sent the bits.
+        mBitsAvailable[throttle_cat] -= bits;
+
+        mBitsSentThisPeriod[throttle_cat] += bits;
+
+        // What if bitsavailable goes negative?
+        // That's OK, because it means someone is banging on the channel,
+        // so we need some time to recover.
+
+        return retval;
+}
+
+
+BOOL LLThrottleGroup::dynamicAdjust()
+{
+        const F32 DYNAMIC_ADJUST_TIME = 1.0f;           // seconds
+        const F32 CURRENT_PERIOD_WEIGHT = .25f;         // how much weight to give to last period while determining BPS utilization
+        const F32 BUSY_PERCENT = 0.75f;         // if use more than this fraction of BPS, you are busy
+        const F32 IDLE_PERCENT = 0.70f;         // if use less than this fraction, you are "idle"
+        const F32 TRANSFER_PERCENT = 0.90f;     // how much unused bandwidth to take away each adjustment
+        const F32 RECOVER_PERCENT = 0.25f;      // how much to give back during recovery phase
+
+        S32 i;
+
+        F64 mt_sec = LLMessageSystem::getMessageTimeSeconds();
+
+        // Only dynamically adjust every few seconds
+        if ((mt_sec - mDynamicAdjustTime) < DYNAMIC_ADJUST_TIME)
+        {
+                return FALSE;
+        }
+        mDynamicAdjustTime = mt_sec;
+
+        S32 total = 0;
+        // Update historical information
+        for (i = 0; i < TC_EOF; i++)
+        {
+                if (mBitsSentHistory[i] == 0)
+                {
+                        // first run, just copy current period
+                        mBitsSentHistory[i] = mBitsSentThisPeriod[i];
+                }
+                else
+                {
+                        // have some history, so weight accordingly
+                        mBitsSentHistory[i] = (1.f - CURRENT_PERIOD_WEIGHT) * mBitsSentHistory[i] 
+                                + CURRENT_PERIOD_WEIGHT * mBitsSentThisPeriod[i];
+                }
+
+                mBitsSentThisPeriod[i] = 0;
+                total += llround(mBitsSentHistory[i]);
+        }
+
+        // Look for busy channels
+        // TODO: Fold into loop above.
+        BOOL channels_busy = FALSE;
+        F32  busy_nominal_sum = 0;
+        BOOL channel_busy[TC_EOF];
+        BOOL channel_idle[TC_EOF];
+        BOOL channel_over_nominal[TC_EOF];
+
+        for (i = 0; i < TC_EOF; i++)
+        {
+                // Is this a busy channel?
+                if (mBitsSentHistory[i] >= BUSY_PERCENT * DYNAMIC_ADJUST_TIME * mCurrentBPS[i])
+                {
+                        // this channel is busy
+                        channels_busy = TRUE;
+                        busy_nominal_sum += mNominalBPS[i];             // use for allocation of pooled idle bandwidth
+                        channel_busy[i] = TRUE;
+                }
+                else
+                {
+                        channel_busy[i] = FALSE;
+                }
+
+                // Is this an idle channel?
+                if ((mBitsSentHistory[i] < IDLE_PERCENT * DYNAMIC_ADJUST_TIME * mCurrentBPS[i]) &&
+                        (mBitsAvailable[i] > 0))
+                {
+                        channel_idle[i] = TRUE;
+                }
+                else
+                {
+                        channel_idle[i] = FALSE;
+                }
+
+                // Is this an overpumped channel?
+                if (mCurrentBPS[i] > mNominalBPS[i])
+                {
+                        channel_over_nominal[i] = TRUE;
+                }
+                else
+                {
+                        channel_over_nominal[i] = FALSE;
+                }
+
+                //if (total)
+                //{
+                //      llinfos << i << ": B" << channel_busy[i] << " I" << channel_idle[i] << " N" << channel_over_nominal[i];
+                //      llcont << " Nom: " << mNominalBPS[i] << " Cur: " << mCurrentBPS[i] << " BS: " << mBitsSentHistory[i] << llendl;
+                //}
+        }
+
+        if (channels_busy)
+        {
+                // Some channels are busy.  Let's see if we can get them some bandwidth.
+                F32 used_bps;
+                F32 avail_bps;
+                F32 transfer_bps;
+
+                F32 pool_bps = 0;
+
+                for (i = 0; i < TC_EOF; i++)
+                {
+                        if (channel_idle[i] || channel_over_nominal[i] )
+                        {
+                                // Either channel i is idle, or has been overpumped.
+                                // Therefore it's a candidate to give up some bandwidth.
+                                // Figure out how much bandwidth it has been using, and how
+                                // much is available to steal.
+                                used_bps = mBitsSentHistory[i] / DYNAMIC_ADJUST_TIME;
+
+                                // CRO make sure to keep a minimum amount of throttle available
+                                // CRO NB: channels set to < MINIMUM_BPS will never give up bps, 
+                                // which is correct I think
+                                if (used_bps < gThrottleMinimumBPS[i])
+                                {
+                                        used_bps = gThrottleMinimumBPS[i];
+                                }
+
+                                if (channel_over_nominal[i])
+                                {
+                                        F32 unused_current = mCurrentBPS[i] - used_bps;
+                                        avail_bps = llmax(mCurrentBPS[i] - mNominalBPS[i], unused_current);
+                                }
+                                else
+                                {
+                                        avail_bps = mCurrentBPS[i] - used_bps;
+                                }
+
+                                //llinfos << i << " avail " << avail_bps << llendl;
+
+                                // Historically, a channel could have used more than its current share,
+                                // even if it's idle right now.
+                                // Make sure we don't steal too much.
+                                if (avail_bps < 0)
+                                {
+                                        continue;
+                                }
+
+                                // Transfer some bandwidth from this channel into the global pool.
+                                transfer_bps = avail_bps * TRANSFER_PERCENT;
+                                mCurrentBPS[i] -= transfer_bps;
+                                pool_bps += transfer_bps;
+                        }
+                }
+
+                //llinfos << "Pool BPS: " << pool_bps << llendl;
+                // Now redistribute the bandwidth to busy channels.
+                F32 unused_bps = 0.f;
+
+                for (i = 0; i < TC_EOF; i++)
+                {
+                        if (channel_busy[i])
+                        {
+                                F32 add_amount = pool_bps * (mNominalBPS[i] / busy_nominal_sum);
+                                //llinfos << "Busy " << i << " gets " << pool_bps << llendl;
+                                mCurrentBPS[i] += add_amount;
+
+                                // CRO: make sure this doesn't get too huge
+                                // JC - Actually, need to let mCurrentBPS go less than nominal, otherwise
+                                // you aren't allowing bandwidth to actually be moved from one channel
+                                // to another.  
+                                // *TODO: If clamping high end, would be good to re-
+                                // allocate to other channels in the above code.
+                                const F32 MAX_BPS = 4 * mNominalBPS[i];
+                                if (mCurrentBPS[i] > MAX_BPS)
+                                {
+                                        F32 overage = mCurrentBPS[i] - MAX_BPS;
+                                        mCurrentBPS[i] -= overage;
+                                        unused_bps += overage;
+                                }
+
+                                // Paranoia
+                                if (mCurrentBPS[i] < gThrottleMinimumBPS[i])
+                                {
+                                        mCurrentBPS[i] = gThrottleMinimumBPS[i];
+                                }
+                        }
+                }
+
+                // For fun, add the overage back in to objects
+                if (unused_bps > 0.f)
+                {
+                        mCurrentBPS[TC_TASK] += unused_bps;
+                }
+        }
+        else
+        {
+                // No one is busy.
+                // Make the channel allocations seek toward nominal.
+
+                // Look for overpumped channels
+                F32 starved_nominal_sum = 0;
+                F32 avail_bps = 0;
+                F32 transfer_bps = 0;
+                F32 pool_bps = 0;
+                for (i = 0; i < TC_EOF; i++)
+                {
+                        if (mCurrentBPS[i] > mNominalBPS[i])
+                        {
+                                avail_bps = (mCurrentBPS[i] - mNominalBPS[i]);
+                                transfer_bps = avail_bps * RECOVER_PERCENT;
+
+                                mCurrentBPS[i] -= transfer_bps;
+                                pool_bps += transfer_bps;
+                        }
+                }
+
+                // Evenly distribute bandwidth to channels currently
+                // using less than nominal.
+                for (i = 0; i < TC_EOF; i++)
+                {
+                        if (mCurrentBPS[i] < mNominalBPS[i])
+                        {
+                                // We're going to weight allocations by nominal BPS.
+                                starved_nominal_sum += mNominalBPS[i];
+                        }
+                }
+
+                for (i = 0; i < TC_EOF; i++)
+                {
+                        if (mCurrentBPS[i] < mNominalBPS[i])
+                        {
+                                // Distribute bandwidth according to nominal allocation ratios.
+                                mCurrentBPS[i] += pool_bps * (mNominalBPS[i] / starved_nominal_sum);
+                        }
+                }
+        }
+        return TRUE;
+}