diff --git a/dom/media/gmp/ChromiumCDMParent.cpp b/dom/media/gmp/ChromiumCDMParent.cpp
index cbb646b4741f..3a8564e993d4 100644
--- a/dom/media/gmp/ChromiumCDMParent.cpp
+++ b/dom/media/gmp/ChromiumCDMParent.cpp
@@ -16,7 +16,6 @@
 #include "MediaPrefs.h"
 #include "mozilla/dom/MediaKeyMessageEventBinding.h"
 #include "mozilla/gmp/GMPTypes.h"
-#include "mozilla/Telemetry.h"
 #include "mozilla/Unused.h"
 #include "AnnexB.h"
 #include "H264.h"
@@ -676,9 +675,6 @@ ChromiumCDMParent::EnsureSufficientShmems(size_t aVideoFrameSize)
     mVideoShmemsActive++;
   }
 
-  mMaxVideoShmemsActive =
-    std::max(mMaxVideoShmemsActive, mVideoShmemsActive);
-
   return true;
 }
 
@@ -1077,12 +1073,7 @@ ChromiumCDMParent::ShutdownVideoDecoder()
   }
   mVideoDecoderInitialized = false;
 
-  GMP_LOG("ChromiumCDMParent::~ShutdownVideoDecoder(this=%p) "
-          "VIDEO_CHROMIUM_CDM_MAX_SHMEMS=%u",
-          this,
-          mMaxVideoShmemsActive);
-  Telemetry::Accumulate(Telemetry::HistogramID::VIDEO_CHROMIUM_CDM_MAX_SHMEMS,
-                        mMaxVideoShmemsActive);
+  GMP_LOG("ChromiumCDMParent::~ShutdownVideoDecoder(this=%p) ", this);
 
   // The ChromiumCDMChild will purge its shmems, so if the decoder is
   // reinitialized the shmems need to be re-allocated, and they may need
diff --git a/dom/media/gmp/ChromiumCDMParent.h b/dom/media/gmp/ChromiumCDMParent.h
index 1e25c481221e..669b0814da1c 100644
--- a/dom/media/gmp/ChromiumCDMParent.h
+++ b/dom/media/gmp/ChromiumCDMParent.h
@@ -178,8 +178,6 @@ protected:
   uint32_t mVideoShmemsActive = 0;
   // Maximum number of shmems to use to return decoded video frames.
   uint32_t mVideoShmemLimit;
-  // High water mark for mVideoShmemsActive, reported via telemetry.
-  uint32_t mMaxVideoShmemsActive = 0;
 
   bool mIsShutdown = false;
   bool mVideoDecoderInitialized = false;
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index 03dc668af24a..79c0b84b2377 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -8596,15 +8596,6 @@
     "description": "Reports whether a navigator.requestMediaKeySystemAccess() was called in a secure context (i.e. on an origin served over HTTPS) or not.",
     "bug_numbers": [1360438]
   },
-  "VIDEO_CHROMIUM_CDM_MAX_SHMEMS": {
-    "record_in_processes": ["main", "content"],
-    "alert_emails": ["cpearce@mozilla.com"],
-    "bug_numbers": [1366639],
-    "expires_in_version": "60",
-    "kind": "enumerated",
-    "n_values": 50,
-    "description": "Counts of the maximum number of shared memory buffers used for transferring video frames between the CDM and Gecko processes during playback of DRM'd video. Reported once per CDMVideoDecoder instance, i.e., once per JavaScript SourceBuffer during playback of video using EME."
-  },
   "MEDIA_EME_REQUEST_DEPRECATED_WARNINGS": {
     "record_in_processes": ["main", "content"],
     "alert_emails": ["cpearce@mozilla.com"],