diff --git a/HISTORY.md b/HISTORY.md
index e4fca51e7..a0f91a494 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,5 +1,10 @@
 # DynamicPPL Changelog
 
+## 0.36.11
+
+Make `ThreadSafeVarInfo` hold a total of `Threads.nthreads() * 2` logp values, instead of just `Threads.nthreads()`.
+This fix helps to paper over the cracks in using `threadid()` to index into the `ThreadSafeVarInfo` object.
+
 ## 0.36.10
 
 Added compatibility with ForwardDiff 1.0.
diff --git a/Project.toml b/Project.toml
index fe4d69ef5..362035eb7 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "DynamicPPL"
 uuid = "366bfd00-2699-11ea-058f-f148b4cae6d8"
-version = "0.36.10"
+version = "0.36.11"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
diff --git a/src/simple_varinfo.jl b/src/simple_varinfo.jl
index abf14b8fc..3ae425896 100644
--- a/src/simple_varinfo.jl
+++ b/src/simple_varinfo.jl
@@ -648,10 +648,12 @@ end
 # Threadsafe stuff.
 # For `SimpleVarInfo` we don't really need `Ref` so let's not use it.
 function ThreadSafeVarInfo(vi::SimpleVarInfo)
-    return ThreadSafeVarInfo(vi, zeros(typeof(getlogp(vi)), Threads.nthreads()))
+    return ThreadSafeVarInfo(vi, zeros(typeof(getlogp(vi)), Threads.nthreads() * 2))
 end
 function ThreadSafeVarInfo(vi::SimpleVarInfo{<:Any,<:Ref})
-    return ThreadSafeVarInfo(vi, [Ref(zero(getlogp(vi))) for _ in 1:Threads.nthreads()])
+    return ThreadSafeVarInfo(
+        vi, [Ref(zero(getlogp(vi))) for _ in 1:(Threads.nthreads() * 2)]
+    )
 end
 
 has_varnamedvector(vi::SimpleVarInfo) = vi.values isa VarNamedVector
diff --git a/src/threadsafe.jl b/src/threadsafe.jl
index 2dc2645de..bd1876a19 100644
--- a/src/threadsafe.jl
+++ b/src/threadsafe.jl
@@ -9,7 +9,18 @@ struct ThreadSafeVarInfo{V<:AbstractVarInfo,L} <: AbstractVarInfo
     logps::L
 end
 function ThreadSafeVarInfo(vi::AbstractVarInfo)
-    return ThreadSafeVarInfo(vi, [Ref(zero(getlogp(vi))) for _ in 1:Threads.nthreads()])
+    # In ThreadSafeVarInfo we use threadid() to index into the array of logp
+    # fields. This is not good practice --- see
+    # https://github.com/TuringLang/DynamicPPL.jl/issues/924 for a full
+    # explanation --- but it has worked okay so far.
+    # The use of nthreads()*2 here ensures that threadid() doesn't exceed
+    # the length of the logps array. Ideally, we would use maxthreadid(),
+    # but Mooncake can't differentiate through that. Empirically, nthreads()*2
+    # seems to provide an upper bound to maxthreadid(), so we use that here.
+    # See https://github.com/TuringLang/DynamicPPL.jl/pull/936
+    return ThreadSafeVarInfo(
+        vi, [Ref(zero(getlogp(vi))) for _ in 1:(Threads.nthreads() * 2)]
+    )
 end
 ThreadSafeVarInfo(vi::ThreadSafeVarInfo) = vi
 
diff --git a/test/threadsafe.jl b/test/threadsafe.jl
index 72c439db8..ededf78b0 100644
--- a/test/threadsafe.jl
+++ b/test/threadsafe.jl
@@ -5,7 +5,7 @@
 
         @test threadsafe_vi.varinfo === vi
         @test threadsafe_vi.logps isa Vector{typeof(Ref(getlogp(vi)))}
-        @test length(threadsafe_vi.logps) == Threads.nthreads()
+        @test length(threadsafe_vi.logps) == Threads.nthreads() * 2
         @test all(iszero(x[]) for x in threadsafe_vi.logps)
     end