diff --git a/.gitlab/.gitlab-ci.yml b/.gitlab/.gitlab-ci.yml
index e1ac9fa06..57ea4d522 100644
--- a/.gitlab/.gitlab-ci.yml
+++ b/.gitlab/.gitlab-ci.yml
@@ -216,7 +216,7 @@ run go tests race:
   script:
     - echo "Running featurebase race tests..."
     - PKG_LIST=$(go list ./... | grep -Ev 'internal/clustertests|simulacraData|batch|idk|v3/dax/test/dax' | paste -s -d, -)
-    - RAMDISK=/mnt/ramdisk go test -race -v -timeout=10m ${PKG_LIST//,/ }
+    - TMPDIR=/mnt/ramdisk go test -race -v -timeout=10m ${PKG_LIST//,/ }
   tags:
     - docker
 
@@ -232,7 +232,7 @@ run go tests:
   script:
     - echo "Running featurebase unit tests..."
     - PKG_LIST=$(go list ./... | grep -Ev 'internal/clustertests|simulacraData|batch|idk|v3/dax/test/dax' | paste -s -d, -)
-    - RAMDISK=/mnt/ramdisk go test -tags=shardwidth22 -timeout=10m -coverprofile=coverage.out -covermode=atomic -coverpkg=${PKG_LIST} ${PKG_LIST//,/ }
+    - TMPDIR=/mnt/ramdisk go test -tags=shardwidth22 -timeout=10m -coverprofile=coverage.out -covermode=atomic -coverpkg=${PKG_LIST} ${PKG_LIST//,/ }
   artifacts:
     paths:
       - coverage.out
diff --git a/Makefile b/Makefile
index a3ff35bea..d482b2f4e 100644
--- a/Makefile
+++ b/Makefile
@@ -24,6 +24,9 @@ BUILD_TAGS +=
 TEST_TAGS = roaringparanoia
 TEST_TIMEOUT=10m
 RACE_TEST_TIMEOUT=10m
+# size in GB to use for ramdisk, ?= so you can override it with env
+# 4GB is not enough for `make test`, 8GB usually is.
+RAMDISK_SIZE ?= 8
 
 export GO111MODULE=on
 export GOPRIVATE=github.com/molecula
@@ -77,13 +80,18 @@ testvsub:
 			echo; echo "999 done testing subpkg $$pkg"; \
 		done
 
-# make a 2GB RAMDisk. Speed up tests by running them with RAMDISK=/mnt/ramdisk
+# make a $(RAMDISK_SIZE)GB RAMDisk. Speed up tests by running
+# them with TMPDIR=/mnt/ramdisk.
 ramdisk-linux:
-	mount -o size=2G -t tmpfs none /mnt/ramdisk
+	mount -o size=$(RAMDISK__SIZE)G -t tmpfs none /mnt/ramdisk
 
-# make a 2GB RAMDisk. Speed up tests by running them with RAMDISK=/Volumes/RAMDisk
+# make a $(RAMDISK_SIZE)GB RAMDisk. Speed up tests by running
+# them with TMPDIR=/Volumes/RAMDisk. This is more important on
+# OS X than it is on Linux, because there's performance issues
+# with fsync on OS X that can make the SSD slow down to moving-platters
+# drive speeds. Oops.
 ramdisk-osx:
-	diskutil erasevolume HFS+ 'RAMDisk' `hdiutil attach -nobrowse -nomount ram://4194304`
+	diskutil erasevolume HFS+ 'RAMDisk' $$(hdiutil attach -nobrowse -nomount ram://$$(expr 2097152 \* $(RAMDISK_SIZE)))
 
 detach-ramdisk-osx:
 	hdiutil detach /Volumes/RAMDisk
diff --git a/translate.go b/translate.go
index 852420abc..2573a14f4 100644
--- a/translate.go
+++ b/translate.go
@@ -289,7 +289,7 @@ func OpenInMemTranslateStore(rawurl, index, field string, partitionID, partition
 		fname = fname[:10]
 	}
 
-	tf, err := os.CreateTemp(os.Getenv("RAMDISK"), fmt.Sprintf("bolt-i%s-f%s-%d-%d-", iname, fname, partitionID, partitionN))
+	tf, err := os.CreateTemp("", fmt.Sprintf("bolt-i%s-f%s-%d-%d-", iname, fname, partitionID, partitionN))
 	if err != nil {
 		return nil, errors.Wrap(err, "making temp file for boltdb key translation")
 	}