diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index cce179d12b29585a404f25518801e19a40e0ad04..3eb5591cdb957c54b4c3ebe8b0ee605cf89c0682 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -2185,7 +2185,8 @@
         <dd>
           An in-memory filesystem, using memory from the host OS.
           The source element has a single attribute <code>usage</code>
-          which gives the memory usage limit in kibibytes. Only used
+          which gives the memory usage limit in KiB, unless units
+          are specified by the <code>units</code> attribute. Only used
           by LXC driver.
           <span class="since"> (since 0.9.13)</span></dd>
         <dt><code>type='bind'</code></dt>
@@ -2251,7 +2252,8 @@
         <code>name</code> attribute must be used with
         <code>type='template'</code>, and the <code>dir</code> attribute must
         be used with <code>type='mount'</code>. The <code>usage</code> attribute
-        is used with <code>type='ram'</code> to set the memory limit in KB.
+        is used with <code>type='ram'</code> to set the memory limit in KiB,
+        unless units are specified by the <code>units</code> attribute.
       </dd>
 
       <dt><code>target</code></dt>
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 6978dc74d31a07e2028bf9aaae5caea118e499e1..b99f23e6ac816ea728af479e22016cae3e854add 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -1699,7 +1699,7 @@
                 <ref name="unsignedLong"/>
               </attribute>
               <optional>
-                <attribute name='unit'>
+                <attribute name='units'>
                   <ref name='unit'/>
                 </attribute>
               </optional>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 8de6a85839b072c8ad8499203f65f1b4957e2559..dd41980495d48dd8f2b654afc63f7ede7fda4192 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5873,7 +5873,7 @@ virDomainFSDefParseXML(xmlNodePtr node,
     char *accessmode = NULL;
     char *wrpolicy = NULL;
     char *usage = NULL;
-    char *unit = NULL;
+    char *units = NULL;
 
     ctxt->node = node;
 
@@ -5929,7 +5929,7 @@ virDomainFSDefParseXML(xmlNodePtr node,
                     source = virXMLPropString(cur, "name");
                 else if (def->type == VIR_DOMAIN_FS_TYPE_RAM) {
                     usage = virXMLPropString(cur, "usage");
-                    unit = virXMLPropString(cur, "unit");
+                    units = virXMLPropString(cur, "units");
                 }
             } else if (!target &&
                        xmlStrEqual(cur->name, BAD_CAST "target")) {
@@ -5999,8 +5999,7 @@ virDomainFSDefParseXML(xmlNodePtr node,
                            usage);
             goto error;
         }
-        if (unit &&
-            virScaleInteger(&def->usage, unit,
+        if (virScaleInteger(&def->usage, units,
                             1024, ULLONG_MAX) < 0)
             goto error;
     }
@@ -6022,7 +6021,7 @@ cleanup:
     VIR_FREE(accessmode);
     VIR_FREE(wrpolicy);
     VIR_FREE(usage);
-    VIR_FREE(unit);
+    VIR_FREE(units);
     VIR_FREE(format);
 
     return def;
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 56739b7bf49c9503fdae74e5fcedf6f3d25789a8..ec4fd4baa870e5df561c629e11bd9638baad7842 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -884,7 +884,7 @@ struct _virDomainFSDef {
     int accessmode; /* enum virDomainFSAccessMode */
     int wrpolicy; /* enum virDomainFSWrpolicy */
     int format; /* enum virStorageFileFormat */
-    unsigned long long usage;
+    unsigned long long usage; /* in bytes */
     char *src;
     char *dst;
     bool readonly;
diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
index 8abaea0f325d1b3545250a97361ca7567a08c845..fca7a203a95e339e73f81ed5aa918942d42e32ac 100644
--- a/src/lxc/lxc_container.c
+++ b/src/lxc/lxc_container.c
@@ -1347,7 +1347,7 @@ static int lxcContainerMountFSTmpfs(virDomainFSDefPtr fs,
     char *data = NULL;
 
     if (virAsprintf(&data,
-                    "size=%lldk%s", fs->usage, sec_mount_options) < 0)
+                    "size=%lld%s", fs->usage, sec_mount_options) < 0)
         goto cleanup;
 
     if (virFileMakePath(fs->dst) < 0) {
diff --git a/tests/domainschematest b/tests/domainschematest
index 0e360caae903fff533235c986741d45db8b7bbd3..9ebf0b9a58043aca2b9d908c3643175ecaf2bdc1 100755
--- a/tests/domainschematest
+++ b/tests/domainschematest
@@ -7,7 +7,7 @@
 DIRS=""
 DIRS="$DIRS domainschemadata qemuxml2argvdata sexpr2xmldata"
 DIRS="$DIRS xmconfigdata xml2sexprdata qemuxml2xmloutdata "
-DIRS="$DIRS lxcxml2xmldata"
+DIRS="$DIRS lxcxml2xmldata lxcxml2xmloutdata"
 SCHEMA="domain.rng"
 
 check_schema "$DIRS" "$SCHEMA"
diff --git a/tests/lxcxml2xmldata/lxc-filesystem-ram.xml b/tests/lxcxml2xmldata/lxc-filesystem-ram.xml
new file mode 100644
index 0000000000000000000000000000000000000000..002fde6ad1539eda326cba0141d41dc2718f650f
--- /dev/null
+++ b/tests/lxcxml2xmldata/lxc-filesystem-ram.xml
@@ -0,0 +1,33 @@
+<domain type='lxc'>
+  <name>demo</name>
+  <uuid>8369f1ac-7e46-e869-4ca5-759d51478066</uuid>
+  <memory unit='KiB'>500000</memory>
+  <currentMemory unit='KiB'>500000</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64'>exe</type>
+    <init>/bin/sh</init>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/libexec/libvirt_lxc</emulator>
+    <filesystem type='ram'>
+        <source usage='1048576'/>
+        <target dir='/mnt/mississippi'/>
+    </filesystem>
+    <filesystem type='ram'>
+        <source usage='1048576' units='bytes'/>
+        <target dir='/mnt/antananarivo'/>
+    </filesystem>
+    <filesystem type='ram'>
+        <source usage='1024' units='KiB'/>
+        <target dir='/mnt/ouagadougou'/>
+    </filesystem>
+    <console type='pty'>
+      <target type='lxc' port='0'/>
+    </console>
+  </devices>
+</domain>
diff --git a/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml b/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml
new file mode 100644
index 0000000000000000000000000000000000000000..d2369a25d1ca9d8eacc2e0969a3da34838294d0d
--- /dev/null
+++ b/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml
@@ -0,0 +1,33 @@
+<domain type='lxc'>
+  <name>demo</name>
+  <uuid>8369f1ac-7e46-e869-4ca5-759d51478066</uuid>
+  <memory unit='KiB'>500000</memory>
+  <currentMemory unit='KiB'>500000</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64'>exe</type>
+    <init>/bin/sh</init>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/libexec/libvirt_lxc</emulator>
+    <filesystem type='ram' accessmode='passthrough'>
+      <source usage='1048576' units='KiB'/>
+      <target dir='/mnt/mississippi'/>
+    </filesystem>
+    <filesystem type='ram' accessmode='passthrough'>
+      <source usage='1024' units='KiB'/>
+      <target dir='/mnt/antananarivo'/>
+    </filesystem>
+    <filesystem type='ram' accessmode='passthrough'>
+      <source usage='1024' units='KiB'/>
+      <target dir='/mnt/ouagadougou'/>
+    </filesystem>
+    <console type='pty'>
+      <target type='lxc' port='0'/>
+    </console>
+  </devices>
+</domain>
diff --git a/tests/lxcxml2xmltest.c b/tests/lxcxml2xmltest.c
index ca05d291f755d4e79595995f7dffad1eb7e40ce3..f8b5959e2162f7133a22183464e126f7a09d8729 100644
--- a/tests/lxcxml2xmltest.c
+++ b/tests/lxcxml2xmltest.c
@@ -131,6 +131,7 @@ mymain(void)
     DO_TEST("systemd");
     DO_TEST("hostdev");
     DO_TEST("disk-formats");
+    DO_TEST_DIFFERENT("filesystem-ram");
 
     virObjectUnref(caps);
     virObjectUnref(xmlopt);