alibaba/Sentinel · error · IllegalStateException

count() is unavailable if minMax() has been called

Error message

count() is unavailable if minMax() has been called

What it means

StatEntryFuncMinMax implements the min/max strategy (stat type 4): it keeps only two ValueRef slots — running max and running min with reference strings — maintained via lock-free CAS loops. It has no occurrence counter, so count(long) is unsupported and throws IllegalStateException.

Source

Thrown at sentinel-core/src/main/java/com/alibaba/csp/sentinel/eagleeye/StatEntryFunc.java:154

            appender.append(lmin.ref);
        }
    }

    @Override
    public Object[] getValues() {
        ValueRef lmax = max.get();
        ValueRef lmin = min.get();
        return new Object[] {lmax.value, lmax.ref, lmin.value, lmin.ref};
    }

    @Override
    public int getStatType() {
        return 4;
    }

    @Override
    public void count(long count) {
        throw new IllegalStateException("count() is unavailable if minMax() has been called");
    }

    @Override
    public void countAndSum(long count, long value) {
        throw new IllegalStateException("countAndSum() is unavailable if minMax() has been called");
    }

    @Override
    public void arrayAdd(long... values) {
        throw new IllegalStateException("arrayAdd() is unavailable if minMax() has been called");
    }

    @Override
    public void arraySet(long... values) {
        throw new IllegalStateException("arraySet() is unavailable if minMax() has been called");
    }

    @Override

View on GitHub (pinned to a3f40ba8e9)

Solutions

1. Remove the count() call for min/max entries; min/max entries track extremes only.
2. If occurrence counts are also needed, maintain a separate count-and-sum entry in the same logger.
3. In generic recorders, branch on getStatType() == 4 to skip count() for min/max entries.

Example fix

// before
func.count(1); // func is StatEntryFuncMinMax -> throws
func.minMax(value, ref);

// after
func.minMax(value, ref);
// counts go to a separate count-and-sum entry
countFunc.countAndSum(1, value);

if (func.getStatType() != 4) { func.count(1); }
func.minMax(value, ref); // always ok on min/max

boolean isMinMax(StatEntryFunc f) { return f.getStatType() == 4; }

When it happens

Trigger: Calling count(n) on an entry created with the minMax strategy — e.g. a throughput counter call left in place after the metric was converted to min/max tracking, or a generic recorder that always counts and additionally records extremes.

Common situations: Metric migrated from counter to latency min/max without removing old count() call sites. Shared recording helper hard-codes count() plus optional extras. Config-driven type change missed in one module.

Related errors

• minMax() is unavailable if countAndSum() has been called
• countAndSum() is unavailable if minMax() has been called
• arrayAdd() is unavailable if minMax() has been called
• arraySet() is unavailable if minMax() has been called
• batchAdd() is unavailable if minMax() has been called

AI-assisted analysis of alibaba/Sentinel@a3f40ba8e9 (2026-08-14). Data as JSON: /api/errors/1ee376ab83205737. Report an issue: GitHub.