diff --git a/src/cgr_gwas_qc/workflow/sub_workflows/sample_qc.smk b/src/cgr_gwas_qc/workflow/sub_workflows/sample_qc.smk
index c4c6baae..969661ea 100644
--- a/src/cgr_gwas_qc/workflow/sub_workflows/sample_qc.smk
+++ b/src/cgr_gwas_qc/workflow/sub_workflows/sample_qc.smk
@@ -344,6 +344,8 @@ use rule relatedness from graf as sample_concordance_graf with:
         rules.graf_extract_fingerprint_snps.output[0],
     output:
         "sample_level/concordance/graf.tsv",
+    resources:
+        mem_mb=lambda wc, attempt, input: max( (attempt+1)* input.size_mb, 1000),
     log:
         "sample_level/concordance/graf.log",